# Patent

## Title
Gas valve with electronic valve proving system

## Abstract

Valve assemblies may be configured to perform a valve proving test as part of an operational cycle of a combustion appliance coupled to the valve assembly. The valve assembly may include a valve body having a fluid path, first and second valves situated in the fluid path, first and second valve actuators, and a pressure sensor in fluid communication with an intermediate volume of the fluid path between the first and second valves. A valve controller may monitor a measure related to a pressure in the intermediate volume. The valve controller may then output a signal if the measure related to the pressure in the intermediate volume meets and/or exceeds a threshold value, where the threshold value is determined based on a measure related to an initial pressure in the intermediate volume and a known test duration.

## Background
RELATED APPLICATIONS
This application is related to U.S. application Ser. No. 13/326,366 filed Dec. 15, 2011 and entitled Gas Valve With Electronic Proof of Closure System, U.S. application Ser. No. 13/326,353 filed Dec. 15, 2011 and entitled Gas Valve With Electronic Valve Proving System, U.S. application Ser. No. 13/326,357 filed Dec. 15, 2011 and entitled Gas Valve with High/Low Gas Pressure Detection, U.S. application Ser. No. 13/326,691 filed Dec. 15, 2011 and entitled Gas Valve With Fuel Rate Monitor, U.S. application Ser. No. 13/326,355 filed Dec. 15, 2011 and entitled Gas Valve With Overpressure Diagnostics, U.S. application Ser. No. 13/326,358 filed on Dec. 15, 2011 and entitled Gas Valve With Valve Leakage Test, U.S. application Ser. No. 13/326,361 filed on Dec. 15, 2011 and entitled Gas Valve With Electronic Cycle Counter, and U.S. application Ser. No. 13/326,523 filed on Dec. 15, 2011 and entitled Gas Valve With Communication Link, all of which are incorporated by reference in their entireties and for all purposes.
TECHNICAL FIELD
The disclosure relates generally to valves, and more particularly, to gas valve assemblies.
BACKGROUND
Valves are commonly used in conjunction with many appliances for regulating the flow of fluid. For example, gas valves are often incorporated into gas-fired appliances to regulate the flow of gas to a combustion chamber or burner. Examples of such gas-fired appliances may include, but are not limited to, water heaters, furnaces, boilers, fireplace inserts, stoves, ovens, dryers, grills, deep fryers, or any other such device where gas control is desired. In such gas-fired appliances, the gas may be ignited by a pilot flame, electronic ignition source, or other ignition source, causing combustion of the gas at the burner element producing heat for the appliance. In many cases, in response to a control signal from a control device such as a thermostat or other controller, the gas valve may be moved between a closed position, which prevents gas flow, and an open position, which allows gas flow. In some instances, the gas valve may be a modulating gas valve, which allows gas to flow at one or more intermediate flow rates between the fully open position and the fully closed position. Additionally or alternatively, valves are used in one or more other applications for controlling a flow (e.g., a flow of a fluid such as a liquid or gas, or a flow of other material).
SUMMARY
This disclosure relates generally to valves, and more particularly, to gas valve assemblies. In one illustrative but non-limiting example, a valve assembly may be configured for controlling fuel flow to a combustion appliance, where the combustion appliance may cycle on and off during a sequence of operational cycles. The valve assembly may, in some cases, perform one or more valve proving tests during an operation cycle and/or between operational cycles to help ensure that the one or more valves properly close.
In one illustrative embodiment, the valve assembly may include a valve body having an inlet port and an outlet port with a fluid path extending between the inlet port and the outlet port. The valve assembly may include a first valve situated in the fluid path between the inlet port and the outlet port, and a second valve situated in the fluid path between the inlet port and the outlet port downstream of the first valve, with an intermediate volume defined between the first valve and the second valve. First and second valve actuators may be included in the valve assembly such that the first and second valve actuators may be capable of moving the first and second valves, respectively, between a closed position that closes the fluid path between the inlet port and the outlet path, and open position.
The valve assembly may include a pressure sensor in fluid communication with the intermediate volume between the first valve and the second valve for sensing a measure related to a pressure in the intermediate volume. A valve controller may be operatively coupled to the first valve actuator, the second valve actuator, and the pressure sensor. In some cases, the valve controller may be configured to identify both the first valve and the second valve are in a closed position, identify a measure related to a pressure change rate in the pressure sensed by the intermediate volume pressure sensor in the intermediate volume, and identify a measure that is related to a leakage rate based at least in part on the measure that is related to the pressure change rate in the intermediate volume and a measure that is related to a volume of the intermediate volume. The valve controller may be further configured to compare the measure related to the leakage rate to a threshold value, and output an alert signal if the measure related to the leakage rate crosses the threshold value.
In some instances, the valve controller may be configured to identify a predetermined duration, close both the first valve via the first valve actuator and the second valve via the second valve actuator, and identify a measure related to an initial pressure in the intermediate volume of the valve body. A threshold for the valve proving test may be determined by the valve controller based at least in part on both the measure related to the initial pressure and the identified predetermined duration. The valve controller may then identify a measure that is related to the pressure in the intermediate volume during the predetermined duration and compare the identified measure related to the pressure in the intermediate volume to the determined threshold value, and output an alert signal if the measure related to the pressure in the intermediate volume crosses the threshold value.
In some instances, a method of performing a valve proving test on a gas valve assembly may include closing both the first valve and the second valve, identifying a measure related to a pressure change rate in the pressure sensed by the intermediate volume pressure sensor, and identifying a measure that is related to a leakage rate based at least in part on the measure that is related to the pressure change rate in the intermediate volume and a measure that is related to a volume of the intermediate volume. Then, the method may include comparing the measure related to the leakage rate to a threshold value, and outputting an alert signal if the measure related to the leakage rate crosses the threshold value.
The preceding summary is provided to facilitate an understanding of some of the innovative features unique to the present disclosure and is not intended to be a full description. A full appreciation of the disclosure can be gained by taking the entire specification, claims, drawings, and abstract as a whole.



BRIEF DESCRIPTION OF THE DRAWINGS
The disclosure may be more completely understood in consideration of the following detailed description of various illustrative embodiments in connection with the accompanying drawings, in which:
FIG. 1 is a schematic perspective view of an illustrative fluid valve assembly;
FIG. 2 is a schematic first side view of the illustrative fluid valve assembly of FIG. 1;
FIG. 3 is a schematic second side view of the illustrative fluid valve assembly of FIG. 1, where the second side view is from a side opposite the first side view;
FIG. 4 is a schematic input side view of the illustrative fluid valve assembly of FIG. 1;
FIG. 5 is a schematic output side view of the illustrative fluid valve assembly of FIG. 1;
FIG. 6 is a schematic top view of the illustrative fluid valve assembly of FIG. 1;
FIG. 7 is a cross-sectional view of the illustrative fluid valve assembly of FIG. 1, taken along line 7-7 of FIG. 4;
FIG. 8 is a cross-sectional view of the illustrative fluid valve assembly of FIG. 1, taken along line 8-8 of FIG. 2;
FIG. 9 is a schematic diagram showing an illustrative fluid valve assembly in communication with a building control system and an appliance control system, where the fluid valve assembly includes a differential pressure sensor connect to a valve controller;
FIG. 10 is a schematic diagram showing an illustrative fluid valve assembly in communication with a building control system and an appliance control system, where the fluid valve assembly includes multiple pressure sensors connected to a valve controller;
FIG. 11 is a schematic diagram showing an illustrative schematic of a low gas pressure/high gas pressure limit control;
FIG. 12 is a schematic diagram showing an illustrative schematic valve control and combustion appliance control, where the controls are connected via a communication link;
FIG. 13 is a schematic diagram showing an illustrative valve control and proof of closure system in conjunction with a combustion appliance;
FIGS. 14-17 are various illustrative schematic depictions of different methods for sensing a position and/or state of a valve within an illustrative valve assembly;
FIGS. 18 and 19 are schematic pressure versus time graphs illustrating pressure thresholds;
FIG. 20 is a schematic flow chart of an illustrative method of performing a valve proving system test;
FIG. 21 is a schematic flow chart of an illustrative method of performing a valve proving system test; and
FIGS. 22A and 22B are schematic flow charts of an illustrative method of performing a valve proving system test.



While the disclosure is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit aspects of the disclosure to the particular illustrative embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure.
DESCRIPTION
The following description should be read with reference to the drawings wherein like reference numerals indicate like elements throughout the several views. The detailed description and drawings show several illustrative embodiments which are meant to be illustrative of the claimed disclosure.
Any descriptors such as first, second, third, fourth, fifth, left right, up, down, bottom, top, are not meant to be limiting unless expressly indicated. Rather, such descriptors may be used to for clarity purposes to indicate how a feature relates to another feature.
Gas valves may be added to fluid path systems supplying fuel and/or fluid to appliances (e.g., burners, etc.) or may be used individually or in different systems. In some instances, gas safety shutoff valves may be utilized as automatic redundant valves. Redundancy is achieved, and often times required by regulatory agencies, by placing at least two safety shutoff valves in series. The aforementioned redundant valves may be separate valves fitted together in the field and/or valves located together in a single valve body, these redundant valves are commonly referred to as double-block valves. In accordance with this disclosure, these and other gas valves may be fitted to include sensors and/or switches and/or other mechanical or electronic devices to assist in monitoring and/or analyzing the operation of the gas valve and/or connected appliance. The sensors and/or switches may be of the electromechanical type or the electronic type, or of other types of sensors and/or switches, as desired.
In some cases, a gas valve assembly may be configured to monitor and/or control various operations including, but not limited to, monitoring fluid flow and/or fluid consumption, electronic cycle counting, overpressure diagnostics, high gas pressure and low gas pressure detection, valve proving system tests, valve leakage tests, proof of valve closure tests, diagnostic communications, and/or any other suitable operation as desired.
Valve Assembly
FIG. 1 is a schematic perspective view of an illustrative fluid (e.g., gas, liquid, etc.) valve assembly 10 for controlling fluid flow to a combustion appliance or other similar or different device. In the illustrative embodiment, the gas valve assembly 10 may include a valve body 12, which may generally be a six sided shape or may take on any other shape as desired, and may be formed as a single body or may be multiple pieces connected together. As shown, the valve body 12 may generally be a six-sided shape having a first end 12a, a second end 12b, a top 12c, a bottom 12d, a back 12e and a front 12f, as depicted in the various views of FIGS. 1-6. The terms top, bottom, back, front, left, and right are relative terms used merely to aid in discussing the drawings, and are not meant to be limiting in any manner.
The illustrative valve body 12 includes an inlet port 14, an outlet port 16 and a fluid path or fluid channel 18 extending between the inlet port 14 and the outlet port 16. Further, valve body 12 may include one or more gas valve ports 20 (e.g., a first valve port 20a and a second valve port 20b, shown in FIGS. 7 and 8) positioned or situated in the fluid channel 18, one or more fuel or gas valve member(s) sometimes referred to as valve sealing member(s) 22 moveable within gas valve ports 20 (e.g., a first valve sealing member 22a within first valve port 20a and a second valve sealing member 22b within second valve port 20b, as shown in FIG. 7), one or more pressure sensor assemblies 24 (as shown in FIG. 8, for example), one or more position sensors 48, and/or one or more valve controllers 26 (as shown in FIG. 8, for example) affixed relative to or coupled to the valve body 12 and/or in electrical communication (e.g., through a wired or wireless connection) with the pressure sensor assemblies 24 and the position sensor(s) 48.
The valve assembly 10 may further include one or more actuators for operating moving parts therein. For example, the valve assembly 10 may have actuators including, but not limited to, one or more stepper motors 94 (shown as extending downward from bottom 12d of valve body 12 in FIG. 1), one or more solenoids 96 (shown as extending upward from top 12c of valve body 12 in FIG. 1), and one or more servo valves 98 (a servo valve 98 is shown as extending upward from top 12c of valve body 12 in FIG. 1-3, where a second servo valve has been omitted), where the servo valve 98 may be a 3-way auto-servo valve or may be any other type of servo valve. Other actuators may be utilized, as desired.
In one illustrative embodiment, the one or more solenoids 96 may control whether the one or more gas valve ports 20 are open or closed. The one or more stepper motors 94 may determine the opening size of the gas valve ports 20 when the corresponding gas valve sealing member 22 is opened by the corresponding solenoid 96. Of course, the one or more stepper motors 94 may not be provided when, for example, the valve assembly 10 is not a “modulating” valve that allows more than one selectable flow rate to flow through the valve when the valve is open.
As shown, the valve body 12 may include one or more sensors and electronics compartments 56, which in the illustrative embodiment, extend from back side 12e as depicted in FIGS. 1, 2 and 4-6. The sensors and electronics compartments 56 may be coupled to or may be formed integrally with the valve body 12, and may enclose and/or contain at least a portion of the valve controllers 26, the pressure sensors assemblies 24, and/or the electronics required for operation of valve assembly 10 as described herein. Although the compartments 56 may be illustratively depicted as separate structures, the compartments 56 may be a single structure part of, extending from, and/or coupled to the valve body 12.
The one or more fluid valve ports 20 may include a first gas valve port 20a and a second gas valve port 20b situated along and/or in communication with the fluid channel 18. This is a double-block valve design. Within each gas valve port 20, a gas valve sealing member 22 may be situated in fluid channel 18 and may be positioned (e.g., concentrically or otherwise) about an axis, rotatable about the axis, longitudinally and axially translatable, rotationally translatable, and/or otherwise selectively movable between a first position (e.g., an open or closed position) and a second position (e.g., a closed or open position) within the corresponding valve port 20. Movement of the valve sealing member 22 may open and close the valve port 20.
It is contemplated that valve sealing member 22 may include one or more of a valve disk 91, a valve stem 92 and/or valve seal 93 for sealing against a valve seat 32 situated in fluid channel 18, as best seen in FIGS. 14-17, and/or other similar or dissimilar components facilitating a seal. Alternatively, or in addition, valve sealing member 22 may include structural features and/or components of a gate valve, a disk-on-seat valve, a ball valve, a butterfly valve and/or any other type of valve configured to operate from a closed position to an open position and back to a closed position. An open position of a valve sealing member 22 may be any position that allows fluid to flow through the respective gas valve port 20 in which the valve sealing member 22 is situated, and a closed position may be when the valve sealing member 22 forms at least a partial seal at the respective valve port 20, such as shown in FIG. 7. Valve sealing member 22 may be operated through any technique. For example, valve sealing member 22 may be operated through utilizing a spring 31, an actuator 30 to effect movement against the spring 31, and in some cases a position sensor 48 to sense a position of the valve sealing member 22.
Valve actuator(s) 30 may be any type of actuator configured to operate the valve sealing member 22 by actuating valve sealing member 22 from the closed position to an open position and then back to the closed position during each of a plurality of operation cycles during a lifetime of the gas valve assembly 10 and/or of the actuator 30. In some cases, the valve actuator 30 may be a solenoid actuator (e.g., a first valve actuator 30a and a second valve actuator 30b, as seen in FIG. 7), a hydraulic actuator, magnetic actuators, electric motors, pneumatic actuators, and/or other similar or different types of actuators, as desired. In the example shown, the valve actuators 30a, 30b may be configured to selectively move valves or valve sealing members 22a, 22b of valve ports 20a, 20b between a closed position, which closes the fluid channel 18 between the inlet port 14 and the outlet port 16 of the valve body 12, and an open position. As discussed, the gas valve assembly 10 of FIGS. 1-8 is an example of a gas safety shutoff valve, or double-block valve. In some cases, however, it is contemplated that the gas valve assembly 10 may have a single valve sealing member 22a, or three or more valve sealing members 22 in series or parallel, as desired.
In some cases, the valve assembly 10 may include a characterized port defined between the inlet port 14 and the outlet port 16. A characterized port may be any port (e.g., a fluid valve port 20 or other port or restriction through which the fluid channel 18 may travel) at or across which an analysis may be performed on a fluid flowing therethrough. For example, if a flow resistance of a valve port 20 is known over a range of travel of the valve sealing member 22, the one of the one or more gas valve ports 20 may be considered the characterized port. As such, and in some cases, the characterized port may be a port 20 having the valve sealing member 22 configured to be in an open position and in a closed position. Alternatively, or in addition, a characterized port may not correspond to the gas valve port 20 having the valve sealing member 22. Rather, the characterized port may be any constriction or feature across which a pressure drop may be measured and/or a flow rate may be determined.
Characterized ports may be characterized at various flow rates to identify a relationship between a pressure drop across the characterized port and the flow rate through the fluid channel 18. In some cases, the pressure drop may be measured directly with one or more pressure sensors 42, 43, 44, and/or 38. In other cases, the pressure drop may be inferred from, for example, the current position of the valve member(s). These are just some examples. In some cases, the relationship may be stored in a memory 37, such as a RAM, ROM, EEPROM, other volatile or non-volatile memory, or any other suitable memory of the gas valve assembly 10, but this is not required.
In some cases, the gas valve assembly 10 may include a flow module 28 for sensing one or more parameters of a fluid flowing through fluid channel 18, and in some instances, determining a measure related to a gas flow rate of the fluid flowing through the fluid channel 18. The flow module 28 may include a pressure block or pressure sensor assembly 24, a temperature sensor 34, a valve member position sensor 48 and/or a valve controller 26, among other assemblies, sensors, and/or systems for sensing, monitoring, and/or analyzing parameters of a fluid flowing through the fluid channel 18, such as can be seen in FIGS. 9 and 10.
It is contemplated that the flow module 28 may utilize any type of sensor to facilitate determining a measure related to a flow rate of a fluid through fluid channel 18, such as a pressure sensor, a flow sensor, a valve position sensor, a temperature sensor, a current sensor, a gas sensor, an oxygen sensor, a CO sensor, a CO2 sensor, and/or any other type of sensor, as desired. In one example, the flow module 28, which in some cases may be part of a valve controller 26, may be configured to monitor a differential pressure across a characterized port, and in some cases, a position of one or more valve sealing members 22 of the gas valve assembly 10. The information from monitoring may be utilized by the flow module 28 to determine and/or monitor the flow rate of fluid passing through the fluid channel 18. For example, the flow module 28 may determine a measure that is related to a gas flow rate through the fluid channel 18 based, at least in part, on the measure that is related to the pressure drop across the characterized port along with the pre-stored relationship in the memory 37. In some cases, the current position of one or more valve sealing members 22 of the gas valve assembly 10 may also be taken into account (e.g. is the valve 30% open, 50% open or 75% open).
In some instances, the flow module 28 may be configured to output the flow rate of fluid passing through the fluid channel 18 to a display or a remote device. In some cases, the flow module 28 may maintain a cumulative gas flow amount passing through the fluid channel 18 (e.g. over a time period), if desired. The measure related to a gas flow may include, but is not limited to, a measure of fuel consumption by a device or appliance that is connected to an outlet port 16 of the gas valve assembly 10.
It is contemplated that the valve controller or valve control block 26 (see, FIG. 8-10) may be physically secured or coupled to, or secured or coupled relative to, the valve body 12. The valve controller 26 may be configured to control and/or monitor a position or state (e.g., an open position and a closed position) of the valve sealing members 22 of the valve ports 20 and/or to perform other functions and analyses, as desired. In some cases, the valve control block 26 may be configured to close or open the gas valve member(s) or valve sealing member(s) 22 on its own volition, in response to control signals from other systems (e.g., a system level or central building control), and/or in response to received measures related to sensed pressures upstream, intermediate, and/or downstream of the characterized valve port(s), measures related to a sensed differential pressure across the characterized valve port(s), measures related to temperature sensed upstream, intermediate, and/or downstream of the characterized valve port(s), and/or in response to other measures, as desired.
The memory 37, which in some cases may be part of or in communication with the valve controller 26, may be configured to record data related to sensed pressures, sensed differential pressures, sensed temperatures, and/or other measures. The valve controller 26 may access these settings and this data, and in some cases, communicate (e.g., through a wired or wireless communication link 100) the data and/or analyses of the data to other systems (e.g., a system level or central building control) as seen in FIGS. 9 and 10. The memory 37 and/or other memory may be programmed and/or developed to contain software to affect one or more of the configurations described herein.
In some instances, the valve controller 26 may be considered a portion of the flow module 28, the flow module 28 may be considered part of the valve controller 26, or the flow module 28 and valve controller 26 may be considered separate systems or devices. Illustratively, the valve controller 26 may be coupled relative to the valve body 12 and one or more gas valve ports 20, where the valve controller 26 may be configured to control a position (e.g., open or closed positions, including various open positions) of the valve sealing member 22 within the valve port 20. In some cases, the valve controller 26 may be coupled to and/or be in communication with local sensors including, but not limited to the pressure sensor assembly 24 (e.g., used for Low Gas/High Gas pressure limit functions, Valve Proving System tests, etc.), a flow sensor (e.g., for measuring gas consumption, etc.), a temperature sensor, 34 (e.g., to monitor temperature of a key component such as an actuator or other component, etc.), a position sensor 48, a current draw sensor (e.g., for sensing the current draw of an actuator or the entire system, etc.), a gas sensor, an oxygen sensor, a carbon monoxide (CO) sensor, a carbon dioxide (CO2) sensor, a cycle sensor and/or cycle counter, timers (e.g., to measure an amount of time to open the valve and/or close the valve), and/or other sensors and assemblies, as desired.
The valve controller 26 may include or may be in communication with one or more remote sensor inputs for receiving one or more sensed parameters form one or more remotely located sensors located outside of the valve body 12, the valve ports 20, and/or valve actuators 30. Illustratively, the one or more remote sensors may include, but are not limited to, one or more of a pressure sensor, a flow sensor, a temperature sensor, a position sensor, a current draw sensor, a gas sensor, an oxygen sensor, a carbon monoxide (CO) sensor, a carbon dioxide (CO2) sensor, a cycle sensor and/or cycle counter, and/or one or more other remote sensors.
In the illustrative embodiment of FIG. 8, the valve controller 26 may be configured to monitor a differential pressure across a characterized port. In some instances, the valve controller 26 may monitor a differential pressure across the fluid valve port 20 and/or monitor a measure related to a pressure upstream of a fluid valve port 20 (e.g., first valve port 20a) and/or a measure related to a pressure downstream of a fluid valve port 20 (e.g., second valve port 20b). The valve controller 26 may also be configured to monitor an axial position of the valve sealing member 22 in the valve port 20 (e.g., see FIGS. 14-17). As a result, the valve controller 26 may determine a flow rate of fluid passing through the characterized port, where the valve controller 26 may determine the flow rate (and sometimes fluid consumption) based, at least in part, on the monitored differential pressure and/or monitored upstream and downstream pressures in conjunction with a pre-characterized relationship between the pressure drop across the characterized port and the flow rate. In some cases, the monitored axial positioning of the valve sealing member 22 may also be taken into account, particularly when the valve sealing member 22 may assume one or more intermediate open positions between the fully closed and fully opened positions. When so provided, the pre-characterized relationship between the pressure drop across the characterized port and the flow rate may depend on the current axial positioning of valve sealing member 22.
In some instances, the valve controller 26 may include a determining block, which may include a microcontroller 36 or the like, which may include or be in communication with a memory 37, such as a non-volatile memory. Alternatively, or in addition, the determining block (e.g. microcontroller 36) may be coupled to or may be configured within the valve control block or valve controller 26. The determining block may be configured to store and/or monitor one or more parameters, which may be used when determining a measure that is related to a fluid flow rate through the fluid channel 18. The determining block (e.g. microcontroller 36) may be configured to use the stored and/or monitored parameters (e.g. the relationship between a pressure drop across a characterized port and the flow rate through the fluid channel 18) stored in the memory 37 to help determine a measure that is related to a fluid flow rate through the fluid path or the fluid channel 18.
Illustratively, the determining block (e.g. microcontroller 36) may be configured to determine and/or monitor a measure (e.g., a flow rate of fluid passing through the characterized port or other similar or different measure, as desired) based, at least in part, on stored and/or monitored measures including, but not limited to, measures related to pressure drop across a characterized valve port or other pressure related measures upstream and downstream of the characterized valve port(s), a temperature of the fluid flowing through the fluid channel 18, and/or a measure related to a current position of the valve sealing member 22 at the gas valve port 20 or the size of an opening at the characterized port. In one example, a determining block (e.g. microcontroller 36) may include non-volatile memory that is configured to store opening curves of the valve assembly 10, where the opening curves may characterize, at least in part, a flow rate as a function of a sensed axial position of valve sealing member 22, and a sensed differential pressure across a characterized valve port 20 or an otherwise determined pressure at or adjacent a characterized valve port 20 (e.g., knowing a set-point of an upstream pneumatic pressure reducing valve (PRV), as the set-point pressure of the PRV may be substantially equal to the pressure at an inlet of the characterized valve port), and may facilitate determining an instantaneous and/or cumulative fluid (e.g., fuel) flow in the fluid channel 18 and/or consumption by an appliance in fluid communication with the valve assembly 10.
It is contemplated that the determining block (e.g. microcontroller 36) may continuously or non-continuously control, store, and/or monitor a position (e.g., an axial or rotary position or open/closed state or other position) of the valve sealing member 22 within the valve port 20, monitor a differential pressure across the characterized port, and/or monitor a temperature upstream and/or downstream of the characterized port. In addition, the microcontroller 36 may continuously or non-continuously determine the flow rate of the fluid passing through the characterized port, where the microcontroller 36 may be configured to record in its memory or in another location, an instantaneous flow rate of fluid flowing through the characterized port, a cumulative flow volume, and/or a determined instantaneous or cumulative (e.g., total) fluid consumption based on the positions of the valve sealing member(s) 22 and determined flow rates at an instant of time or over a specified or desired time period. In addition, the determining block (e.g. microcontroller 36) may be configured to report out the instantaneous flow rate, cumulative flow volume, total or cumulative fluid consumption over a given time period, and/or other determination and/or valve assembly conditions. The determining block (e.g. microcontroller 36) may report the instantaneous flow rate, cumulative flow rate, total or cumulative consumption of the fluid flowing through the characterized port, and/or other determination and/or valve assembly conditions to a system display 52 of an overall system controller 50 (e.g., a building/industrial automation system (BAS/IAS) controller), an appliance display 62 of an appliance/system controller 60 where the appliance may be configured to receive the flowing fluid, a display adjacent gas valve assembly 10, or any other display, device, controller and/or memory, as desired.
In some instances, the valve controller 26 may include or be in communication with a valve actuator 30, which in conjunction with the stepper motor 94 or other device is configured to position the valve sealing member 22 in the valve port 20. The valve actuator 30 and/or the stepper motor 94 may be in communication with the microcontroller 36 of the valve controller 26, and the microcontroller 36 may be configured to control, monitor, and/or record the position (e.g., axial position, radial position, etc.) of the valve sealing member 22 within the valve port 20 through the valve actuator 30 (e.g., the valve actuator 30 may be configured to effect the locking (e.g., the valve actuator 30 OFF) or the unlocking (e.g., the valve actuator 30 ON) of the valve sealing member 22 in a particular position) and the stepper motor 94 (e.g., stepper motor 94 may be configured to adjust the position of the valve sealing member 22 when it is not locked in a particular position), or through only the stepper motor 94. Alternatively, or in addition, the microcontroller 36 may be configured to monitor and record the position of the valve sealing member 22 within the valve port 20 through a connection with a position sensor 48 or through other means.
The valve controller 26 may include an I/O or communications interface 110 with a communication protocol for transmitting data to and/or otherwise communicating with one or more remote device(s) that may be located remotely from valve assembly 10 (e.g., a combustion appliance including controller 60 located remotely from valve assembly 10, a remote display, an electronic access tool or key, and/or other remote devices). The communications interface 110 may be a wired or wireless communication interface, where the wired or wireless communication interface 110 may be configured to be compatible with a predetermined communication bus protocol or other communication protocol. A wired link may be low voltage (e.g. 24V, 5V, 3V, etc.), which may reduce certain issues related to line-voltage wiring schemes. Illustratively, communications interface 110, using the predetermined communication bus protocol or other communication protocol, may be configured to output and/or communicate one or more valve conditions, one or more measures related to valve conditions, one or more conditions related to a fluid flow through the fluid channel 18, and/or one or more diagnostic parameters, conditions or events, to a device located adjacent or remote from the valve assembly 10.
In an illustrative example of monitoring parameters sensed by sensors of or in communication with a valve assembly, the microcontroller 36 of the valve controller 26 may continuously or non-continuously monitor and record the position (e.g., axial position, radial position, etc.) of valve sealing member 22 within the valve port 20 through the valve actuator 30 and the stepper motor 94, and the microcontroller 36 may indicate the sensed and/or monitored position of the valve sealing member 22 within the valve port 20 as a prescribed position of valve sealing member 22. The prescribed position of the valve sealing member 22 may be the position at which the valve sealing member 22 was and/or is to be located, whereas a position of the valve sealing member 22 sensed by the position sensor system 48 may be considered an actual position of the valve sealing member 22 within the valve port 20.
In the example, the valve controller 26 may be configured to perform electronic operational cycle counting or may include an electronic counter configured to count each operational valve cycle of the valve sealing members 22 during, for example, the lifetime of the gas valve assembly 10 or during some other time period. In some cases, the microprocessor 36 of the valve controller 26 may be configured to monitor a total number of operational cycles (e.g., the number of times the fuel valve sealing members 22 are operated from a closed position to an open position and back to a closed position) of the valve ports 20 and measures related thereto. In some cases, the microprocessor 36 may store such data in a non-volatile memory, such as the memory 37, sometimes in a tamper proof manner, for record keeping and/or other purposes. The microprocessor 36 may monitor the number of cycles of the valve sealing members 22 in one or more of several different manners. For example, the microprocessor 36 may monitor the number of cycles of the valve sealing members 22 by monitoring the number of times the first main valve switch 72 and/or the second main valve switch 74 are powered or, where one or more control signals may be provided to the fuel valve actuator(s) 30 controlling when the fuel valve actuator(s) 30 selectively moves (e.g., opens or closes) the valve sealing member(s) 22, the microprocessor 36 may monitor the one or more control signals.
The valve controller 26, in some cases, may monitor the main valve switches 72, 74 by receiving signals directly from a device located remotely from the valve assembly 10 on which the main valve switches 72, 74 may be located (e.g. see FIGS. 11-12). Switches ((main valve switches 72, 74 and safety switch 70 (discussed below)) may be any mechanism capable of performing a switching function including, but not limited to, relays, transistors and/or other solid state switches and circuit devices and/or other switches. The valve controller 26 may include an electrical port, sometimes separate from a communications interface 110 (discussed below), for receiving one or more control signals from the device located remotely from valve assembly 10. The one or more control signals received via the electrical port may include, but are not limited to: a first valve port 20a control signal that, at least in part, may control the position of the first valve sealing member 22a via the first valve actuator 30a, and a second valve port 20b control signal that, at least in part, may control the position of the second valve sealing member 22b via the second valve actuator 30b. 
As an alternative to monitoring control signals, or in addition, microprocessor 36 may monitor the number of cycles of valve sealing members 22 by monitoring data from a position sensor 48. For example, microprocessor 36 of valve controller 26 may monitor position sensor 48 and record the number of times valve sealing members 22 are in an open position after being in a closed position and/or the number of times valve sealing members 22 are in a closed position after being in an open position and/or the number of times valve sealing members are operated from a close position to an open position and back to a closed position. These are just some examples. Further, if valve controller 26 is operating valve sealing members 22, valve controller 26 may monitor the number of operational cycles by counting its own control signals sent to valve actuators 30 and/or stepper motors 94.
The non-volatile memory, which may maintain and/or store the number of operational valve cycles, may be positioned directly on, or packaged with, valve body 12 (e.g., on or within memory of microcontroller 36) and/or may be accessible by the valve controller 26. Such storage, placement, and/or packaging of valve cycle data may allow for replacement of components in the overall system (e.g., the an appliance control 60, etc.) without losing the valve cycle data. In an illustrative instance, the valve cycle data may be securely stored, such that it may not be tampered with. For example, the valve cycle data may be stored in the memory 37 (e.g., non-volatile memory or other memory) of the valve controller 26 and the valve cycle data and/or other valve assembly 10 data may be password protected.
The microcontroller 36 of valve assembly 10 may be configured to compare a count of a total number of operational cycles of valve sealing members 22 to a threshold number of operational cycles. In an instance where the counted number of operational cycles of the valve sealing member(s) 22t approaches, meets, or exceeds the threshold number of cycles, the microcontroller 36 may initiate a warning and/or request a switch 69 in a limit string 67 to open and thus, remove or cut power to the valve switches 72, 74 and fuel valve actuator(s) 30. Alternatively, or in addition, the microcontroller 36 may send a signal to initiate an alarm and/or put the system in a safety lockout, or the microcontroller 36 may be configured to take other action as desired. Illustratively, the microcontroller 36 may be configured to prevent fuel valve actuator(s) 30 from allowing the valve sealing member(s) 22 to open after the total number of operational cycles meets and/or exceeds the threshold number of operational cycles. In some instances, the threshold number of cycles may be related to the number of cycles for which the valve assembly 10 is rated (e.g., a maximum number of cycles before failures might be expected, etc.) or related to any other benchmark value. In addition, the microcontroller 36 may be configured to perform other diagnostics based on analyzing captured operational cycle data, where the other diagnostics may include number of cycles, time duration of cycles, and similar or different diagnostics, as desired.
In addition to the communication interface 110 being configured to output information to a device located adjacent or remote from the valve assembly 10, the communication interface 110 may be configured to receive one or more inputs from the remote device or an adjacently positioned device. Illustrative inputs may include, but are not limited to: an acknowledgement of reception of one or more of the valve conditions, a user setting, a system setting, a valve command, and/or other similar or dissimilar input.
In some instances, the valve controller 26 may communicate through the I/O interface or communication interface 110 with a remotely located output block 46, where the output block 46 may display and/or output a determined measure related to fluid flow rate through the fluid channel 18, sometimes along with other data, information and controls sent from the valve controller 26 (see, for example, FIGS. 9 and 10). The output block 46 may include a display and/or other remote systems, and the microcontroller 36 may be configured to send measures to a device control system 60 or building automation system or overall system controller 50 of the output block 46 for further monitoring and/or analysis. As discussed, the I/O interface may include a wired and/or wireless interface between the valve controller 26 (e.g., microcontroller 36) and the output block 46 systems (e.g., the building automation system or the overall system controller 50, the combustion appliance management system 60, handheld device, laptop computer, smart phone, etc.), where the connection between the valve controller 26 may or may not be made with the communication link 100 (e.g., the communication link 100 could, but need not be, the one and only one communication link).
In an illustrative operation, the valve controller 26 may be utilized in a method for communicating information between the valve assembly 10 and a combustion appliance controller 60, where the combustion appliance controller 60 may be associated with a combustion appliance (e.g., a device separate from, and possibly remotely relative to valve assembly 10) for which the valve assembly 10 may control a flow of fuel. The operation may include sensing, with one or more sensor (e.g., pressure sensor assembly 24), one or more sensed parameters within the fluid channel 18 of the valve assembly 10. The sensed parameter may be stored in the memory 37 (e.g., non-volatile memory or other memory) of the valve controller 26. The valve controller 26 may determine one or more valve conditions (e.g., a safety event condition or other valve condition) based on the one or more sensed parameters. For example, the valve controller 26 may compare the one or more sensed parameters to a threshold parameter to determine one or more valve conditions. If one or more valve conditions have been determined, the valve controller 26 may be configured to send information that may be related to the one or more determined valve conditions from valve assembly 10 to the combustion appliance controller 60 (or other controller or device) across a communication link or bus 100 connected to a communications interface 110.
In one example, upon receiving one or more determined valve conditions, such as a safety event condition, the combustion appliance controller 60 (or other controller or device) may be configured to open the safety switch 70, such that power to a valve control signal that is coupled to one or more valve actuators 30 is cut, thereby automatically closing one or more valve ports 20 (e.g., closing valve sealing member(s) 22 of valve port(s) 20). In some cases, the safety switch 70 may be controlled by an algorithm in the combustion appliance controller 60, where an output of the algorithm is affected by information passed via the communication link 100. Additionally, or in the alternative, other feedback signals may affect an output of the algorithm, where the other feedback signals may or may not be passed via the communication link 100 and may or may not originate from the valve assembly 10.
In other illustrative operations, a low gas pressure/high gas pressure event may be reported from the valve controller 26 to the combustion appliance controller 60. In response to receiving a reported low gas pressure/high gas pressure event, the combustion appliance controller 60 may be configured to open the safety switch 70. Further, in cases where a proof of closure event is reported to the combustion appliance controller 60 prior to ignition of the combustion appliance, an ignition sequence may not be started. In certain other instances where a Valve Proving System (VPS) sequence test is being performed, a combustion appliance controller 60 may use reported results of the VPS sequence test to make an evaluation. For example, if in the evaluation of the VPS test it were determined that a valve was leaking, the appliance controller 60 might be programmed to open safety switch 70, to initiate a safety lockout, to initiate an alarm, and/or to take any other similar or dissimilar measure.
In other scenarios, the valve assembly 10 may be used as a control valve and in that case, the valve controller 26 may send a signal to the combustion appliance controller 60 indicative of a valve position, and the combustion appliance controller 60 may respond accordingly. These other scenarios, for example, may be applied in parallel positioning system applications, low fire switch applications, auxiliary switch applications, etc. Additionally, it is contemplated that the valve controller 26 may interact with remote devices in other similar and dissimilar manners within the spirit of this disclosure.
The pressure block or pressure sensor assembly 24 may be included in the flow module 28, as seen in FIGS. 9 and 10, and/or the pressure sensor assembly 24 may be at least partially separate from the flow module 28. The pressure sensor assembly 24 may be configured to continuously or non-continuously sense pressure or a measure related to pressure upstream and/or downstream of a characterized port and/or along other portions of the fluid channel 18. Although the pressure sensor assembly 24 may additionally, or alternatively, include a mass or volume flow meter to measure a flow of fluid through the fluid channel 18, it has been contemplated that such meters may be more expensive and difficult to place within or outside the valve assembly 10; thus, a useful, relatively low cost alternative and/or additional solution may include placing the pressure sensors 38, 42, 43, 44 and/or other pressure sensors within, about and/or integrated in the valve body 12 of the valve assembly 10 to measure the fluid flow through the fluid channel 18, the pressures at the input and output ports, and/or other similar or different pressure related measures. The pressure sensors 38, 42, 43, 44 may include any type of pressure sensor element. For example, the pressure sensor element(s) may be MEMS (Micro Electro Mechanical Systems) pressure sensors elements or other similar or different pressure sensor elements such as an absolute pressure sense element, a gauge pressure sense element, or other pressure sense element as desired. Example sense elements may include, but are not limited to, those described in U.S. Pat. Nos. 7,503,221; 7,493,822; 7,216,547; 7,082,835; 6,923,069; 6,877,380, and U.S. patent application publications: 2010/0180688; 2010/0064818; 2010/00184324; 2007/0095144; and 2003/0167851, all of which are hereby incorporated by reference.
In some cases, the pressure sensor assembly 24 may include a differential pressure sensor 38 for measuring a differential pressure drop across a characterized valve port 20, or across a different characterized port, as seen in FIG. 9. A pressure sensor assembly 24 including a differential pressure sensor 38, may be exposed to both a first pressure 38a upstream of a characterized valve port and a second pressure 38b downstream of the characterized valve port. The differential pressure sensor 38 may send a measure related to the sensed differential pressure to the microcontroller 36 of the valve controller 26, as seen from the diagram of FIG. 9. The microcontroller 36 may be configured to monitor the differential pressure across the characterized port with the differential pressure measures sensed by the differential pressure sensor 38.
Alternatively, or in addition, an illustrative pressure sensor assembly 24 may include one or more first pressure sensors 42 upstream of a characterized valve port and one or more second pressure sensors 43 downstream of the characterized valve port, where the first and second pressure sensors 42, 43 may be in fluid communication with the fluid channel 18 and may be configured to sense one or more measures related to a pressure upstream and a pressure downstream, respectively, of the characterized valve port, as seen in FIG. 10. Where a second valve port (e.g., the second valve port 20b) may be positioned downstream of a first characterized valve port (e.g. the first valve port 20a) and forming an intermediate volume 19 between the first and second valve ports, the pressure sensor assembly 24 may include one or more third pressure sensors 44 in fluid communication with the intermediate volume 19, which may sense one or more measures related to a pressure in the intermediate volume 19. Where two characterized ports are utilized, the first pressure sensors 42 may be upstream of both characterized ports, second pressure sensors 43 may be downstream of both characterized ports, and the third pressure sensors 44 may be downstream from the first characterized port and upstream from the second characterized, but this is not required (e.g., first and second pressure sensors 42, 43 may be used to estimate the pressure drop across the valves). Additionally, or in the alternative, one or more differential pressure sensors 38 may be utilized to estimate the pressure drop across the first characterized port and/or the second characterized port. It is further contemplated that valve ports 20 may not be characterized ports.
The pressure sensors 42, 43, 44 may be configured to send each of the sensed measure(s) directly to the microcontroller 36. The microcontroller 36 may be configured to save the sensed measures and/or related information to the memory 37 (e.g., non-volatile memory or other memory), and may perform one or more analyses on the received sensed measures. For example, the microcontroller 36, which may be a portion of the flow module 28 and/or the valve controller 26, may determine a measure that is related to a fluid flow rate through the fluid path based, at least in part, on the received sensed measures related to pressure upstream of the characterized port and on the received sensed measures related to pressure downstream of the characterized port.
Where a valve assembly 10 includes one or more valve ports 20, the pressure sensor assembly 24 may include the first pressure sensor 42 positioned upstream of the first valve port 20a at or downstream of the inlet port 14, as seen in FIG. 11. In addition, or alternatively, the pressure sensor assembly 24 may include a second pressure sensor 43 positioned downstream of the second valve port 20b at or upstream from the outlet port 16. The valve assembly 10 may further include one or more third pressure sensors 44 downstream of the first valve port 20a and upstream of the second valve port 20b. The pressure sensors 42, 43, 44 may be configured to sense a pressure and/or a measure related to the pressure in the fluid channel 18, and to communicate the sensed measures to the valve controller 26, which is physically coupled to or positioned within the valve body 12. Where multiple pressure sensors 42, 43, 44 exist at or near one or more location (e.g., upstream of the valve ports 20, intermediate of the valve ports 20, downstream of the valve ports 20, etc.) along the fluid channel 18, at least one of the multiple pressure sensors may be configured to sense pressures over a pressure sub-range different from a sub-range over which at least one other of the multiple pressure sensors at the location may be configured to sense pressure, but this is not required. In some cases, and as shown in FIG. 8, the various pressure sensors may be mounted directly to a corresponding circuit board, such that when the circuit board is mounted to the valve body 12, the pressure sensor is in fluid communication with a corresponding fluid port in the valve body 12.
In some instances, such arrangements of pressure sensors 38, 42, 43, 44 within valve assembly 10, along with the connection between the valve controller 26 and the pressure sensors 38, 42, 43, 44 may be used to emulate functions of high gas pressure (HGP) and low gas pressure (LGP) switches, which traditionally require wires and further housings extending to and from and/or attached to the valve body 12. When the electronics and elements of the valve assembly 10 are configured to emulate LGP/HGP switches, gas-valve wiring connections and interactions may be at least partially avoided, eliminated or simplified. In some instances, such configuration of the valve controller 26 and the pressure sensors 38, 42, 43, 44 may reduce manual operations (e.g., manually adjusting a mechanical spring or other device of conventional high gas pressure (HGP) and low gas pressure (LGP) switches), and allow for a more precise fitting with the electronics of the valve assembly 10.
In some cases, the pressure sensor assembly 24 may include one or more absolute pressure sensors 54 in communication with the microcontroller 36. The absolute pressure sensor 54 may sense an atmospheric pressure adjacent the gas valve assembly 10, and may be configured to communicate and transfer data related to the sensed atmospheric pressure to the microcontroller 36. The microcontroller 36 may take into account the atmospheric pressure from the absolute pressure sensor 54 when determining the flow rate of fluid flowing through the characterized port and/or an estimate of fuel consumption by an attached appliance and/or when determining threshold values. Other sensors may be included in valve assembly 10, for example, one other type of sensor may be a barometric pressure sensor.
As discussed, the valve assembly 10 and the flow module 28 thereof may include temperature sensor(s) 34, as seen in FIGS. 9-11. The temperature sensor 34 may be positioned within the valve body 12 so as to be at least partially exposed to the fluid channel 18 and configured to sense a temperature of a fluid (e.g., gas or liquid) flowing through the fluid channel 18 and/or any other temperature in the fluid channel 18. The temperature sensor 34 may have a first temperature sensor 34a at least partially exposed to the fluid channel 18 upstream of a characterized valve port, and/or a second temperature sensor 34b at least partially exposed to the fluid channel 18 downstream of the characterized valve port, as seen in FIGS. 9 and 10. When there is a first valve port and a second valve port (e.g., valve ports 20a, 20b), there may be a third temperature sensor 34c in fluid communication with intermediate volume 19 between the first and second characterized valve ports, if desired. The sensed temperature measure may be used by flow module 28 to, for example, compensate, correct, or modify a determined measure (e.g., a density of a fluid) that is related to, for example, a fluid flow rate of fluid flowing through the fluid channel 18, which may help improve the accuracy of the flow rate calculation. In operation, the temperature sensor 34 (e.g., any or all of temperatures sensors 34a, 34b, 34c) may communicate a sensed temperature measure directly or indirectly to the valve controller 26 and/or the memory 37 (e.g., non-volatile memory or other memory) of the valve controller 26 (e.g., the memory in a microcontroller 36 or memory in another location) and/or the flow module 28. The valve controller 26 may, in turn, utilize the sensed temperature to help increase the accuracy of a determined flow rate of fluid passing through a characterized port and/or increase the accuracy of a calculated fluid and/or fuel consumption quantity, as desired, and store the calculated flow rate of fluid passing through a characterized port and/or the calculated fluid and/or fuel consumption quantity in the memory 37 (e.g., non-volatile memory or other memory). Additionally, or in the alternative, in some instances the pressure sensors 38, 42, 43, 44 may utilize built-in temperature sensors that are used to internally compensate the pressure sensor over the operating temperature range. In such instances, the temperature reading may be accessible at the pressure sensor output (e.g., a digital communication bus) or at another location.
The flow module 28 of valve assembly 10 may further include a position sensor system that may be configured to continuously or discontinuously sense at least one or more of an axial position, a rotary position, and/or a radial position, of the valve sealing member 22 within or about the fluid valve port 20. In some cases, the position sensor system may include more than one position sensors 48, such that each position sensor 48 may monitor a sub-range of a valve's total travel. Moreover, the position sensor system may be utilized as a proof of closure switch system. The position sensor(s) 48 of the position sensor system may be situated or positioned in valve body 12 at or about a valve port 20. For example, and in some instances, the position sensor(s) 48 may be fluidly isolated from the fluid channel 18 (e.g., fluidly isolated from the fluid channel 18 by the valve body 12), and radially spaced from an axis upon which a valve sealing member(s) 22 may axially and/or rotationally translate between a closed position and an open position, as seen in FIGS. 14-17.
An illustrative gas valve assembly 10 may include a first valve port 20a and a second valve port 20b (see FIG. 7), and a first position sensor 48a monitoring the first valve sealing member 22a and a second position sensor 48b monitoring the second valve sealing member 22b, where the position sensors 48a, 48b may be separate devices or may share an enclosure and/or other parts. In the illustrative instance, the first position sensor 48a may be fluidly isolated from the fluid channel 18 and radially spaced from a first axis of the first valve port 20a, and the second position sensor 48b may be fluidly isolated from the fluid channel 18 and radially spaced from a second axis of second valve port 20b (see FIGS. 14-17).
As discussed above, the position sensor 48 may be configured to detect a measure that is related to whether the valve sealing member 22 is in an open or closed position and/or a measure related to an intermediate position of the valve sealing member 22 within the fluid valve port 20. In one example, the position sensor(s) 48 may be configured to provide a proof of closure (POC) sensor(s) for the valve port(s) 20 (e.g., the first valve port 20a and/or the second valve port 20b).
Where the valve sealing member(s) 22 have a range of travel (e.g., rotationally and/or axially) within the valve port(s) 20, the position sensor(s) 48 may be configured to sense a current position of the valve sealing member(s) 22 anywhere along the range of travel of the valve sealing member(s) 22. The position sensor 48 may then send (e.g., through electronic or other communication) sensed positioning data of the measure related to the position of the valve sealing member 22 to the determining block and/or microcontroller 36 and/or the memory 37 (e.g., non-volatile memory or other memory) of the valve controller 26 and/or the flow module 28, where the microcontroller 36 may be configured to monitor the axial position of the valve sealing member 22 within the valve port 20 through the position sensor system 48.
In some instances, the valve controller 26 may include an electronic circuit board and/or a wired or wireless communication link 100 may facilitate communication between the position sensor(s) 48 and the electronic circuit board or other device of the valve controller 26. The valve controller 26 may be configured to further pass on positioning information to remote devices through communication lines (e.g., the communication link 100) and/or display positioning data of the valve sealing member 22 on one or more displays 76 attached to the valve assembly 10 and/or the remote devices, as seen in FIG. 13. The valve controller 26 may indicate a closed or open position of the valve sealing member 22 or a degree (e.g., 10%, 20%, 30%, etc.) of an opening of the valve sealing member 22 with one or more visual indicators on or comprising the display(s) 76, as seen in FIG. 13, such as one or more light emitting diodes (LEDs) acting as a visual indication of a valve state and/or position, liquid crystal displays (LCDs), a touch screen, other user interfaces and/or any other display interfacing with or displaying information to a user.
In some instances, the position sensor system may include one or more switches 64 (e.g., a first switch 64a and a second switch 64b, where the switch(es) 64 may be or may include relays or other switch types such as FETs, TRIACS, etc.) having one or more switched signal paths 66 and one or more control inputs 68 (e.g., a first control input 68a and a second control input 68b), as seen in FIG. 13. Illustratively, one switch 64 may be utilized for multiple position sensors 48, or more than one switch 64 may be utilized for multiple position sensors (e.g., in a 1-1 manner or other manner), as desired. The control input 68 may set the state of the switched signal paths 66 to a first state or a second state or another state, as desired. As depicted in FIG. 13, the valve controller 26 may be coupled to the position sensor(s) 48, and may control input 68 of switch 64, where both the valve controller 26 and the position sensors 48 may be isolated from fluid communication with the fluid channel 18. In some instances, the valve controller 26 may be configured to set the state of the switched signal path 66 to the first state when the first position sensor 48a senses that a first valve port 20a is not closed or the first valve sealing member 22a is not in a closed position, and to a second state when position sensor 48 senses that a first valve port 20a is closed or the first valve sealing member 22a is in a closed position. Similarly, the valve controller 26 may be configured to set the state of the switched signal path 66 to the first state when the second sensor 48b senses that the second valve port 20b is not closed or the second valve sealing member 22b is not in a closed position, and to a second state when the position sensor 48 senses that a second valve port 20b is closed or the second valve sealing member 22b is in a closed position. In the alternative, the valve controller 26 may be configured to set the state of the switched signal path 66 to the first state when at least one of the first and second sensors valve ports 20a, 20b are not closed or at least one of the first and second valve sealing members 22a, 22b are not in a closed position, and to a second state when the position sensor 48 senses that both first and second valve ports 20a, 20b are closed or both the first and second valve sealing members 22a, 22b are in closed positions. Similar or identical or different processes, as desired, may be utilized for each position switch 64 and control input 68.
Illustratively, the valve sealing member(s) 22 may include a sensor element 80, and position sensor(s) 48 may include one or more transducer or field sensors 82. For example, valve sealing member(s) 22 may include a sensor element 80 (e.g., a magnet when using a field sensor 82, a ferrous core when using a linear variable differential transformer (LVDT) 84, or other sense element, and/or similar or dissimilar indicators) secured relative to and translatable with valve sealing member(s) 22. Position sensor(s) 48 may include one or more field sensors 82 (e.g., magnetic field sensors, a LVDT 84, Hall Effect sensors or other similar or dissimilar sensors), as seen in FIGS. 14-15. Field sensor 82 may be positioned within valve body 12 or may be positioned exterior to valve body 12 and radially spaced from a longitudinal axis of the valve port(s) 20 and/or the valve sealing member(s) 22. The position sensor(s) 48 may be positioned so as to be entirely exterior to the fluid channel 18. The meaning of entirely exterior of the fluid channel 18 may include all position sensors 48 and all electronics (e.g., wires, circuit boards) connected to the position sensor(s) 48 being exterior to fluid channel 18. Where the position sensor(s) 48 includes an LVDT, the LVDT may be positioned concentrically around and radially spaced from the valve sealing member(s) 22, as shown in FIG. 15, and/or the axis of LVDT may be spaced radially and parallel from the valve sealing members 22.
In some cases, a strain gauge 86, as depicted in FIG. 16, or other electromechanical sensor may also be utilized to sense a position of the valve sealing member 22 within an interior of the fluid channel 18 from a position fluidly exterior of the fluid channel 18 by sensing a strain level applied by the spring 31 in communication with valve sealing member 22. Alternatively, or in addition, the valve sealing member(s) 22 may include one or more visual indicators 88 (e.g., a light reflector or other visual indicators), and the position sensor(s) 48 may include one or more optical sensors 90, as seen in FIG. 17, where visual indicators may be any indicators configured to be viewed by optical sensors through a transparent window 87 sealed with an o-ring or seal 89 or through another configuration, such that optical sensors 90 may determine at least whether the valve sealing member(s) 22 is/are in a closed or open position. Where a visual position indicator 88 is utilized, and in some cases, a user may be able to visually determine when the valve sealing member(s) 22 is not in a closed position.
As may be inferred from the disclosure, the position sensor 48 may in some instances operate by detecting a position of a valve sealing member 22 and/or optionally the valve stem 92 or the like within a valve assembly 10 having a valve body 12, where the valve sealing member 22 may be translatable with respect to the valve port 20 of the valve body 12 along a translation or longitudinal axis “A” within a valve port 20. In some cases, the sensor element 80, affixed relative to the valve sealing member 22, may be positioned within the interior of the valve body 12 and may optionally fluidly communicate with the fluid channel 18; however, the position sensor 48 may be isolated from the fluid channel 18 and/or positioned exterior to the valve body 12. In an illustrative embodiment, the valve sealing member 22 may be positioned at a first position within an interior of the valve port 20 along translation axis A. The first position of the valve sealing member 22 may be sensed with position sensor 48 by sensing a location of a sensor element 80 secured relative to the valve sealing member 22 with the position sensor 48. Then, the position sensor 48 may automatically or upon request and/or continuously or discontinuously, send the sensed location and/or open or closed state of the valve sealing member 22 to the valve controller 26.
It is contemplated that the valve controller 26 may electronically calibrate the closed position of the valve sealing member 22 and/or the valve stem 92. Such a calibration may store the position of the valve sealing member 22 and/or the valve stem 92 when the valve sealing member 22 and/or the valve stem 92 is in a known closed position (e.g. such as during installation of the valve assembly 10). During subsequent operation, the position of the valve sealing member 22 and/or the valve stem 92 can be compared to the stored position to determine if the valve sealing member 22 and/or the valve stem 92 is in the closed position. A similar approach may be used to electronically calibrate other positions of the valve sealing member 22 and/or the valve stem 92 (e.g. fully open position, or some intermediate position), as desired.
Valve Proving System Test
The valve controller 26 may be configured to perform an electronic valve proving system (VPS) test on the valve assembly 10, where all or substantially all of the structure required for the VPS may be integrated directly into the valve assembly 10. When so provided, the direct integration may allow sensors and electronics needed for VPS testing to share a common housing. Alternatively or in addition, the VPS testing may be initiated by the appliance controller 60 (e.g., a burner controller).
In an illustrative operation, a VPS test may be performed on a valve assembly 10 that is coupled to a non-switched gas source, or other gas source, that is under a positive pressure during the VPS test to test the gas valve assembly 10 for leaks. Alternatively, or in addition, VPS tests may be performed on valve assemblies 10 in other configurations.
The valve assembly 10 may be in communication with the combustion appliance controller 60 or other device, and may at least partially control a fuel flow to a combustion appliance through the fluid channel 18. Illustratively, the combustion appliance may cycle on and off during a sequence of operational cycles, where at least some of the operational cycles may include performing a VPS test prior to and/or after igniting received fuel during the corresponding operational cycle. For example, VPS tests may be performed on each valve port 20 prior to igniting received fuel during a corresponding operational cycle, VPS tests may be performed on each valve port 20 after a call for heat is satisfied (e.g., at the very end of an operational cycle), or a VPS test may be performed on a first valve port 20a prior to igniting received fuel during a corresponding operational cycle and on a second valve port 20b after a call for heat is satisfied. Illustratively, VPS tests may be automated processes that occur at every, or at least some, operational cycle(s) (e.g., once the VPS test has been set up by a field installer or at the original equipment manufacturer, the testing may not require the end user to participate in any way).
The structural set up of the valve assembly 10 for a VPS test may include the valve controller 26 being in communication with a pressure sensor 44 that may be in fluid communication with the intermediate volume 19 between the two valve ports 20 (e.g., the first valve port 20a and the second valve port 20b, as seen in FIG. 8). Where the valve controller 26 may be in communication with the pressure sensor 44, the valve controller 26 may be configured to determine a measure related to a pressure (e.g., an absolute pressure, a gauge pressure, a differential pressure, and/or other measure) in the intermediate volume 19 during each VPS test performed as part of at least some of the operational cycles of the combustion appliance, or at other times. Alternatively, or in addition, the valve controller 26 may be in communication with one or more of the inlet pressure sensor 42, the outlet pressure sensor 43, and/or other pressure sensors (e.g., the differential pressure sensor 38 and/or other sensors), where the pressure sensors 38, 42, 43 sense measures related to the pressure upstream of the first port 20a and downstream of the second port 20b, respectively, and communicate the sensed measures to the valve controller 26. Although pressure sensors downstream of the ports (e.g., the pressure sensor(s) 43) may not be directly used to determine whether a valve is leaking, the downstream pressure sensor(s) 43 may, in some cases, monitor outlet pressure before, during, and/or after leakage tests of the valves and, in some cases, may facilitate determining which valve is leaking if a valve leakage is detected.
Due to the timing of the VPS test(s) before and/or after operational cycles, or both, the test(s) may be achieved in an amount of time consistent with the useful operation of an individual appliance (e.g., a short amount of time, 10-15 seconds, 5-30 seconds, or a longer amount of time) which may depend on one or more of the inlet pressure, initial pressure in the intermediate volume 19, size of the intermediate volume 19, volume of the appliance combustion chamber, length of time of the appliance pre-purge cycle, firing rate of the appliance burner, the leakage threshold level (e.g., allowed leakage level/rate), etc. In some instances, a VPS test duration may be fixed and saved in memory of the valve assembly 10, the combustion appliance, and/or saved in other memory. For example, a VPS test duration may be fixed in memory of or accessible by a controller (e.g., the valve controller 26, the combustion appliance controller 60, or other controller) in a permanent manner, for a period of time, for a number of cycles, for each VPS test occurring before the VPS test duration is changed by a user or an automated system, and/or in any other suitable manner. Illustratively, a fixed VPS test duration may be modified by a user in the field by interacting with the valve controller 26 and/or the combustion appliance controller 60.
Fixed VPS test duration or other predetermined duration (e.g., a duration during which pressure may be monitored in the intermediate chamber or other duration) may mitigate or eliminate the need to calculate a VPS test duration or other predetermined duration based on one or more factors at the time of initial install of a valve assembly 10, such as, but not limited to, an expected inlet gas or fuel pressure or an allowed leakage rate. Rather, and in some cases, an installer may set the fixed duration at a desired duration without performing any calculations. Additionally or alternatively, when a fixed VPS test duration or other predetermined duration is utilized, an allowed leakage rate (e.g., as set by a standards setting body, a manufacturer, other entity, an installer or a user) may, in some cases, be adjusted during the life of the valve assembly 10 or combustion appliance. In some instances, the allowed leakage rate may be adjusted by a user by interacting with the valve controller 26 and/or the combustion appliance controller 60.
In some cases, a VPS test duration or other predetermined duration may be fixed at the time of initial install of a valve assembly 10 by saving the set VPS test duration or other predetermined duration to the memory 37 (e.g., non-volatile memory or other memory) of the valve assembly 10 or other memory that may be located remotely, but in communication with the valve controller 26. Alternatively or in addition, the VPS test duration or other predetermined duration may be stored in memory of the combustion appliance. During the install of the valve assembly 10, an installer may program the VPS test duration or other predetermined duration in the valve controller 26 and/or the combustion appliance controller 60 to a fixed duration for all or substantially all required leakage levels and/or for all expected gas or fuel pressures in the fluid channel 18 (e.g., an inlet gas or fuel pressure upstream of the valve ports 20). In some cases, the VPS test duration or other predetermined duration may also be modified later by interacting with the valve controller 26 at the valve assembly 10 or remote from the valve assembly 10.
In some cases, one or more VPS thresholds may be programmed into the valve controller 26. In some cases, one or more VPS thresholds (e.g., a first and a second VPS sub-test threshold values) may be calculated. In some cases, the valve controller 26 may be configured to calculate one or more VPS thresholds based on one or more parameters and, in some instances, the valve controller 26 may be configured to store the VPS thresholds (e.g., VPS sub-test threshold values or other VPS test threshold values) in a memory for later use. The one or more parameters that the valve controller 26 may consider if it is determining a VPS test threshold may include, but are not limited to, a sensed pressure (e.g., a sensed pressure in the intermediate volume, an inlet pressure, or other pressure), a sensed temperature, a max flow rate of the system, a number of ON-OFF cycles operated up to a point in time, a volume of the fluid channel 18, a volume of the intermediate volume 19, an altitude of valve assembly 10 (e.g., for calculating and/or estimated an atmospheric pressure at the valve assembly 10 or for other purposes), a barometric pressure, an absolute pressure, a gas type (e.g., density), ANSI requirements, EN requirements, other agency requirements, an allowed VPS test duration, an allowed pressure measuring duration, and how small of a leak is to be detected (e.g., an allowed leakage rate, etc). Further, in the event that more than two sub-tests are performed as part of the VPS test, the valve controller 26 may utilize more threshold values than first and second VPS sub-test threshold values, if desired.
In some instances, one or more of the VPS thresholds may be determined or calculated for a VPS test, and may be used each time the VPS test is executed. Alternatively, one or more VPS thresholds may be re-determined or re-calculated before each of one or more VPS tests are executed. In one illustrative example, one or more VPS thresholds for a VPS test may be determined from a set VPS duration (e.g., a test duration or a duration less than a test duration), a known volume of the intermediate volume 19 of the valve (e.g., which may be programmed into the valve controller by a user and/or at the manufacturer), a specified leakage level sometimes per a safety standard or other standard, and/or a measure related to gas or fuel pressure provided at the inlet of the valve. Since the VPS test duration or other predetermined duration, the volume of the intermediate volume 19, an altitude of the valve assembly 10, and the specified leakage level (e.g., an allowed leakage level) may be known to the valve controller 26 (e.g., saved in memory 37 or other memory), the valve controller 26 may identify a measure related to a gas or fuel pressure in the fluid channel 18 before, during, or after a particular VPS test and can then calculate or determine one or more VPS threshold values for the particular VPS test.
FIGS. 18 and 19 are schematic pressure versus time graphs depicting pressure thresholds for pressure measured in the intermediate volume 19 of a valve assembly during a VPS test. FIG. 18 depicts a graph where the intermediate volume is initially pressurized to a high pressure PH at time=0, where the VPS test is testing leakage through the second valve port 20b and PH may be equal to a pressure upstream of the first valve port 20a or other pressure indicative of a pressurized state in the intermediate volume 19. Illustratively, the threshold pressure value (PTHRESHOLD-H) when the intermediate volume 19 is in a pressurized state is at some pressure less than the pressure PH. In such a pressurized state of the intermediate volume 19, and in one example, PTHRESHOLD-H may be calculated from the following illustrative equation:

PTHRESHOLD-H=PH−(dP/dt)*T  (1)

where dP/dt is the allowed change in pressure rate in the intermediate volume, and T is the predetermined duration over which pressure is monitored in the intermediate volume during the VPS test. The dP/dt value may represent an allowed leakage rate through the second valve, given the intermediate volume of the valve. For example, dP/dt may be proportional to the ratio of the allowed leakage rate to the intermediate volume. Pressure in the intermediate volume during the predetermined duration T is represented by line 150 in FIG. 18.

In some instances, a pressure warning threshold PTHRESHOLD-WH may be calculated from equation (1), where dP/dt is a value that is less than the dP/dt that corresponds to the allowed leakage rate, to give a user a warning when the pressure in the intermediate volume 19 may be changing in a manner that indicates there may be a leak in the valve ports 20, but not to the extent that the valve assembly 10 needs to be shut down. Illustratively, a pressure warning threshold may assist in identifying degradation of the valve assembly 10 by providing an indication to a user during a VPS test that valve assembly 10 is beginning to leak prior to a VPS test in which operation of the valve assembly 10 needs to be shut down, as shown in line 160
FIG. 19 depicts a graph where the intermediate volume is initially pressurized to a pressure PL at time=0, where the VPS test is testing leakage through the first valve port 20a and PL may be equal to a local atmospheric pressure or pressure downstream of the second valve port 20b or other pressure indicative of a depressurized state in the intermediate volume 19. Illustratively, the threshold pressure value (PTHRESHOLD-L) when the intermediate volume 19 is in a depressurized state is at some pressure greater than the pressure PL. In such a depressurized state of the intermediate volume 19, and in one example, PTHRESHOLD-L may be calculated from the following illustrative equation:

PTHRESHOLD-L=PL+(dP/dt)*T  (2)

where dP/dt is the allowed change in pressure rate in the intermediate volume, and T is the predetermined duration over which pressure is monitored in the intermediate volume during the VPS test. the dP/dt value may represent an allowed leakage rate through the first valve, given the intermediate volume of the valve. For example, dP/dt may be proportional to the ratio of the allowed leakage rate to the intermediate volume. Pressure in the intermediate volume during the predetermined duration T is represented by line 170, in FIG. 19.

In some instances, a pressure warning threshold PTHRESHOLD-WL may be calculated from equation (2), where dP/dt is less than the dP/dt that corresponds to the allowed leakage rate, to give users a warning when the pressure in the intermediate volume 19 may be changing in a manner that indicates there may be a leak in the valve ports 20, but not to the extent that the valve assembly needs to be shut down. As discussed above, a pressure warning threshold may assist in identifying degradation of the valve assembly 10 by providing an indication to a user during a VPS test that the valve assembly 10 is beginning to leak prior to a VPS test in which operation of the valve assembly 10 needs to be shut down, as shown in line 160.
In some cases, the VPS test duration or other predetermined duration may not be used in calculating the threshold(s) for a VPS test. For example, as an allowed leakage level (e.g., an allowed leakage rate) may translate to an allowed rate of pressure change (dP/dt) during a VPS test, the one or more VPS thresholds may be set to be independent of the VPS test duration and may be or may primarily be a function of atmospheric pressure, allowed leakage rates, and/or a volume size of the intermediate volume 19 of the valve assembly 10.
Illustratively, an equation for an allowed leakage level may be:

Qcalculated=dP/dt*V/Patm*3600  (3)

where Qcalculated is the measured leakage rate in mass flow volume of liters/hour, dP/dt is a determined slope of a measured pressure over time (e.g., a differential pressure) in Pascals/second, V is the volume of the intermediate volume 19, Patm is the atmospheric pressure in Pascals, and 3600 represents the number of seconds in an hour. Although particular units are disclosed, other units may be utilized as desired. The volume of the intermediate volume 19 and the atmospheric pressure may, generally, be considered constants in this equation. Thus, from equation (3), an allowed leakage level/rate (provided by a safety standard or otherwise) may be used as a VPS threshold, and a measured change of pressure in the intermediate volume over time (dP/dt) may be entered into equation (3) to obtain Qcalculated, which may be compared to the VPS threshold value to determine whether the valve assembly 10 passes the VPS test.

Alternatively, or in addition, a VPS threshold may be a change of pressure over time (dP/dt) determined from equation (3), where Qcalculated is equal to an allowed leakage level and dP/dt is solved for by the controller 26 to determine the VPS threshold value. Then, a measured change of pressure in the intermediate volume over time may be directly compared to the determined VPS threshold value to determine if the valve assembly 10 passes the VPS test.
In some cases, an intermediate pressure, or a measure related thereto, in the intermediate volume may be measured by the inlet pressure sensor 42, by the outlet pressure sensor 43, by the intermediate pressure sensor 44, and/or by other sensors. In instances when the intermediate pressure sensor 44 measures a measure related to the intermediate pressure in the intermediate volume 19, the measure related to the initial pressure may be sensed or identified before both the first valve port 20a and the second valve port 20b are closed (e.g., the first valve port 20a may be opened and the second valve port 20b may be closed), after both the first valve port 20a and the second valve port 20b are closed (e.g., the second valve port 20b is closed and the first valve port 20a is closed after gas or fuel fills the intermediate volume), or both to allow the gas or fuel to flow into the intermediate volume 19 adjacent the intermediate pressure sensor 44 and maintain an inlet pressure. When the inlet pressure sensor 42 is used to provide a measure related to the initial pressure in the fluid channel 18 (e.g., inlet gas or fuel pressure or some other measure), the measure related to the initial pressure may be measured at any time with respect to a VPS test, including, but not limited to, before both the first valve port 20a and the second valve port 20b are closed, after both the first valve port 20a and the second valve port 20b are closed, or both. When the outlet pressure sensor 43 is used to provide a measure related to the initial pressure in the intermediate volume 19, the measure related to the gas or fuel pressure in the fluid channel 18 may be measured when both of the first valve port 20a and the second valve port 20b are in an opened position.
Once a VPS test has been initiated by one or more of the valve controller 26 and the appliance controller 60, the valve controller 26 may determine a threshold value, in a manner similar to as discussed above, and/or perform one or more other tasks related to the VPS test. For example, after initiating a VPS test, the valve controller 26 may identify a predetermined duration associated with the VPS test; measure, sense, or identify a measure related to a fuel pressure (e.g., an inlet gas or fuel pressure or other measure) or initial pressure in the intermediate volume 19; and/or determine one or more threshold values for the VPS test (e.g., based on one or more of the identified measure related to the fuel pressure or an initial pressure in the intermediate volume and the identified predetermined duration). The determined threshold values may then be saved in memory of or in communication with the valve controller 26 and used for comparison against an identified measure related to the pressure in the intermediate volume during the VPS test. In some instances, one or more thresholds (e.g., a first threshold, a second threshold, a third threshold, a fourth threshold, and/or one or more other thresholds) may be determined and saved in the memory 37 for use with the current VPS test or sub-tests of the current VPS test and/or for later use in subsequent VPS tests or sub-tests of VPS tests.
In an illustrative example, the valve controller 26 may include the memory 37 (e.g., non-volatile memory or other memory) that stores previously determined first VPS threshold value (e.g., for comparing to a pressure rise in the intermediate volume 19 or elsewhere) and a second VPS threshold value (e.g., for comparing to a pressure decay in the intermediate volume or elsewhere) utilized in performing a VPS test. Alternatively, or in addition, the memory may be located at a position other than in the valve controller 26, such as any remote memory that may be in communication with the valve controller 26. Such VPS thresholds may be used during subsequent VPS tests, or the VPS thresholds may be recalculated for use during a subsequent VPS test, as desired.
During a VPS test, a measure that is related to the pressure in the intermediate volume 19 may be measured, determined, and/or identified. In some cases, the measure that is related to the pressure in the intermediate volume 19 may be sensed via a pressure sensor that is exposed to the intermediate volume 19. The valve controller 26 may further be configured to compare the measured, determined, and/or identified measure related to a pressure in the intermediate volume 19 (e.g. an absolute pressure, a gauge pressure, a pressure change rate, or other measure) to a first threshold value during a first valve leakage test, and/or to compare the measure that is related to a pressure in the intermediate volume 19 (e.g., an absolute pressure, a gauge pressure, a pressure change rate, or other measure) to a second threshold value during a second valve leakage test. After or while comparing the measure related to the pressure in the intermediate volume 19 to one or more of the threshold values, the valve controller 26 may output an alert signal or other signal if the measure meets and/or exceeds (e.g., crosses, etc.) the corresponding threshold value
The VPS test may be initiated by commanding the valve actuators 30 to open and/or close in a desired sequence. This sequence may be initialized and/or controlled through the valve controller 26 and/or through the combustion appliance controller 60. When the VPS test is controlled by the valve controller 26, the setup of the VPS settings may occur at a display/user interface 76 on board the valve itself or at a remote display (e.g., displays 52, 62 or other displays). When the VPS sequence is initialized and controlled remotely (e.g., remote from the valve controller 26) through the combustion appliance controller 60, the valve controller 26 may be configured to detect if the VPS test or another test is occurring by monitoring gas valve assembly 10 and signals communicated to and/or from the valve assembly 10.
When the VPS test is to be actuated or initiated at or through the combustion appliance controller 60, the setup of the VPS settings may occur at a remote display (e.g., displays 52, 62 or other display(s)). The valve controller 26 may monitor the valve actuators 30a, 30b, a first control signal (MV1) controlling the first valve actuator 30a and a second control signal (MV2) controlling the second valve actuator 30b, and/or the states of the valve ports 20a, 20b (e.g., by monitoring the output of the position sensor(s) 48) to identify if the VPS test is occurring. The first and second control signals (MV1 and MV2) may be actuated by the combustion appliance controller 60 in communication with the valve assembly 10 or by the valve controller 26 or by a field tool in communication with the valve controller 26 or any other tool or individual in communication with the valve assembly 10. Although the field tool and/or other tools may most often be used for actuating the first and second control signals (MV1 and MV2) in a valve leakage test, such similar or different tools may be used to operate a VPS test or for system level diagnostics and/or troubleshooting by a trained appliance technician in the field.
An illustrative method 200 of performing a VPS test, as shown in FIG. 20, may include closing 210 both the first valve port 20a and the second valve port 20b and identifying 212 a measure that is related to a pressure change rate in the pressure sensed by the intermediate volume pressure sensor 44. The method 200 may include identifying 214 a measure related to a leakage rate. In one example, the measure related to a leakage rate may be based at least in part on the measure that is related to the pressure change rate in the intermediate volume and/or a measure that is related to the volume of the intermediate volume 19. The measure related to the identified leakage rate may be compared 216 to a threshold value (e.g., an allowed leakage rate associated with a safety standard or other allowed leakage rate). An alert may then be outputted 218 if the measure related to the leakage rate meets and/or exceeds (e.g., crosses) the threshold value.
An illustrative method 300 of performing a VPS test, as shown in FIG. 21, may include identifying 310 a predetermined duration (e.g., a VPS test duration or a sub-test duration of the VPS test duration programmed into the valve controller 26 or other test duration) and closing 312 the first valve port 20a and the second valve port 20b. In the method 300, a measure related to an initial pressure in the intermediate volume 19 may be identified 314 and a threshold value may be determined 316. The threshold value may be at least partially based on and/or related to one or more of the identified measure related to the initial pressure in the intermediate volume and the identified predetermined duration. Then, a pressure in the intermediate volume 19 of the valve assembly 10 may be identified 318 at some time after the initial pressure in the intermediate volume is determined and the identified pressure in the intermediate volume 19 may be compared 320 to the determined threshold value. If the pressure in the intermediate volume 19 crosses the determined threshold value, the valve controller 26 or other feature of the valve assembly may output 322 an alert signal.
In some instances, VPS tests may include performing 410 a first VPS sub-test and performing 440 a second VPS sub-test, as shown in method 400 in FIGS. 22A and 22B. In method 400, the valve controller 26 may cause, perform, and/or identify a first predetermined sequence (e.g., the first VPS test) 410, as shown in FIG. 22A. In performing 410 the first VPS sub-test, the first valve actuator 30a may open 412 the first valve port 20a (if not already opened) and the second valve actuator 30b may then close 414 the second valve port 20b (if not already closed) to pressurize the intermediate volume 19 between the first valve port 20a and the second valve port 20b. The first valve actuator 30b may then close 416 the first valve port 20a to seal the pressurized intermediate volume 19. In some cases, a predetermined duration associated with the first predetermined sequence may be identified 418.
The valve controller 26 may cause, perform and/or identify this first predetermined sequence as a first sub-test 410 of a VPS test with the identified first predetermined duration. While performing the first VPS sub-test, a first measure of an initial pressure in the intermediate volume 19 may be identified 420 and a first VPS sub-test threshold value may be determined 422 (e.g., according to one of the threshold value determining techniques described herein or in another manner). Illustratively, the threshold value may be determined 422 based at least partially on one or more of the first measure of the gas pressure and the identified first test duration. In one or more other instances, the first VPS sub-test threshold value may be determined based on one or more other measures.
A measure related to the pressure (e.g., the pressure or a measure derived therefrom) in the intermediate volume 19 of the valve assembly may be identified 424 at some time after the initial pressure is identified and the valve controller 26 may be configured to compare 426 the measure that is related to the pressure in the intermediate volume 19 (e.g., a pressure, a pressure change rate, or other measure) to the determined first VPS sub-test threshold value prior to, during, and/or after the first sub-set VPS duration. After or while comparing the measure related to the pressure in the intermediate volume 19 to the first sub-test threshold value, the valve controller 26 may output 428 a first alert signal if the measure meets and/or exceeds (e.g., crosses, etc.) the first sub-test threshold value. The valve controller 26 may be configured to output the signal over the communication bus 100 or using a simple pair of contacts (e.g., relay contacts that close when a measured pressure surpasses a threshold pressure value) at or in communication with the appliance controller 60, one or more of a local display, a remote device 50, 60 and/or a remote display 52, 62 of the remote device(s) 50, 60.
The first sub-test of the VPS test may be configured to at least detect a leaking second valve port 20b. The outputted first alert signal may indicate, or may cause to be indicated, a valve leakage within the valve assembly 10 (e.g., including an indication of which valve port 20 is leaking) and/or a measure of the magnitude of the valve leakage. If a leak is detected or a first alert signal sent, the valve controller 26, the combustion appliance controller 60, or other controller may disable operation of the valve assembly 10 in response to the alert signal, where disabling operation of the valve assembly 10 may include closing both the first valve port 20a and the second valve port 20b. 
In addition to identifying the first sub-test of a VPS test, the valve controller 26 may cause, perform, or identify the following second predetermined sequence (e.g., the second VPS test) 440, as shown in the method 400 of FIG. 22B. In performing the second predetermined sequence 440, the second valve actuator 30b may open 442 the second valve port 20b (if not already opened) and the first valve actuator 30a may then close 444 the first valve port 20a (if not already closed) to depressurize the intermediate volume 19 between the first valve port 20a and the second valve port 20b. The second valve actuator 30a may then close 446 the second valve port 20b to seal the depressurized intermediate volume 19. In some cases, a predetermined duration associated with the second predetermined sequence may be identified 448.
The valve controller 26 may cause or identify this second predetermined sequence as a second sub-test of a VPS test with a second predetermined duration that may be the same or different duration than the first predetermined duration. While performing the second VPS sub test, a second measure of an initial pressure in the intermediate volume 19 may be identified 450 and a second VPS sub-test threshold value may be determined 452 (e.g., according to one of the threshold value determining techniques described herein or in another manner). Illustratively, the second VPS sub-test threshold value may be determined based at least partially on one or more of the second measure of the gas pressure and the identified second test duration. In one or more other instances, the second VPS sub-test threshold value may be determined based on one or more other measures.
A measure related to the pressure in the intermediate volume 19 may be identified 454 or determined by the valve controller 26 at some time after identifying the initial pressure and the valve controller 26 may be configured to compare 456 the identified measure that is related to the pressure in intermediate volume 19 to the determined second VPS sub-test threshold value (e.g., where the second VPS sub-test threshold value is the same as or different than the first sub-test threshold value) prior to, during, or after a second predetermined duration. As contemplated, the first VPS sub-test and the second VPS sub-test of the VPS test may be performed in any order, as desired.
After or while comparing the identified measure related to the pressure in the intermediate volume 19 to the second sub-test threshold value, the valve controller 26 may output 458 a second alert signal if the measure meets and/or exceeds (e.g., crosses, etc.) the second sub-test threshold value. The valve controller 26 may be configured to output the second alert signal to one or more of a local display, a remote device 50, 60 and/or a remote display 52, 62 of the remote device(s) 50, 60.
The second sub-test of the VPS test may be configured to at least detect a leaking first valve port 20a. Illustratively, the outputted second alert signal may indicate, or may cause to be indicated, a valve leakage within the valve assembly 10 (e.g., which valve port 20 is leaking) and/or a measure of the magnitude of the valve leakage. If a leak is detected or a second alert signal sent, the valve controller 26, the combustion appliance controller 60, or other controller may disable operation of the valve assembly 10 in response to the alert signal, where disabling operation of the valve assembly 10 may include closing both the first valve port 20a and the second valve port 20b. 
A VPS test performed on the valve assembly 10 that may be similar to the VPS tests described above may include opening one of the first and second valve port 20a, 20b with the other of the first and second valve ports 20a, 20b remaining or being closed. After opening one of the first and second valve ports 20a, 20b, closing the opened valve to close both valve ports 20a, 20b such that a first initial gas pressure may be present in intermediate volume 19. An intermediate pressure sensor 44 may continuously or discontinuously sense a pressure in the intermediate volume 19, including the first initial pressure therein, and send the sensed pressures to the valve controller 26. The initial pressure in the intermediate volume 19 may be sensed at any time, for example, the initial pressure may be sensed after opening one of the valve ports 20a, 20b and before closing that opened valve port 20a, 20b. The valve controller 26 may monitor (e.g., continuously or discontinuously), over time, the pressure in the intermediate volume 19 and determine or identify a first measure that is related to a pressure change rate within the intermediate volume 19 while both of the valve ports 20a, 20b are in a closed position. After determining or identifying the first measure that is related to a pressure change rate within the intermediate volume 19, the valve controller 26 may compare the determined first measure related to a pressure change rate in the intermediate volume 19 to a first threshold value stored in the valve controller 26. The valve controller 26 may then output to a display and/or remote device 50, 60 or other device an output signal that is related to the first measure related to the pressure change rate (e.g., a determined pressure change in the intermediate volume 19, or other determined measure), where outputting the output signal may also include storing the determined first measure related to the pressure change rate in the memory 37 (e.g., non-volatile memory or other memory) on the valve controller 26. Optionally, the valve controller 26 may output the output signal or an alert output signal if the determined or identified first measure meets and/or exceeds (e.g., crosses, etc.) the first threshold value. The output signal, however, may convey any information, as desired. For example, the output signal may convey information related to when (e.g. time stamp) the determined measure that is related to the pressure change rate meets and/or exceeds a threshold value, or other information related to or not related to the pressure in the intermediate volume 19. In an alternative, or in addition, to providing the output signal, a visual and/or audible indicator may be provided to indicate if the valve assembly 10 passed or failed the VPS test.
In addition, or as an alternative, the first and/or second valve port 20a, 20b may be manipulated such that a second or different initial gas pressure may be present in the intermediate volume 19 while the first and second valve ports 20a, 20b are in the closed position. For example, the second valve port 20b may be closed, then the first valve port 20a may be opened to pressurize the intermediate volume 19 and then closed to seal in the second initial pressure. The second initial pressure may be substantially different than the first initial gas pressure, as the first initial pressure may be associated with a depressurized state of the intermediate volume 19 and the second initial pressure may be associated with a pressurized state of the intermediate volume 19, for example. Similar to above, the intermediate pressure sensor 44 may sense pressure within the intermediate volume 19 and communicate the sensed pressure and measures related to the sensed pressures to the valve controller 26. The valve controller 26 may monitor (e.g., continuously or discontinuously), over time, the pressure in the intermediate volume 19 and determine a second measure that is related to a pressure change rate within the intermediate volume 19 while both the valve ports 20a, 20b are in the closed position.
After determining the second measure that is related to a pressure change rate within the intermediate volume 19, the valve controller 26 may compare the determined second measure related to a pressure change rate in the intermediate volume 19 to a second threshold value stored in the valve controller 26. The valve controller 26 may then output to a display and/or remote device 50, 60 or other device an output signal that is related to the second measure related to a pressure change rate, where outputting the output signal may also include storing the determined second measure related to the pressure change rate in the memory 37 (e.g., non-volatile memory or other memory) on the valve controller 26. Optionally, the valve controller 26 may output the output signal or a different output signal (e.g., an output signal including an alert) if the determined second measure meets and/or exceeds (e.g., crosses, etc.) the second threshold value. The output signal, however, may convey any information and the outputted signals may be outputted in any situation. Further, the output signal may be configured to provide, or cause to be provided, a visual and/or audible indicator to indicate if the valve assembly 10 passed and/or failed the VPS test.
The steps of the illustrative VPS test may be performed once such as when the gas valve assembly 10 is installed or during routine maintenance, and/or the steps may be repeated during each combustion cycle, or during one or more combustion cycles, of a combustion appliance. In any case, the valve controller 26 or other device, or even a user, may identify a trend in the stored determined measures related to the pressure change rate in the intermediate volume 19 or in other data sensed, calculated, and/or stored during the valve leakage tests. A determined trend may be used for any of many purposes, for example, a trend may be used to predict when the valve will require replacement and/or servicing, and/or to make other predictions. Further, a VPS test and/or leakage test may be initiated and/or operated dependent on or independent of an attached device (e.g., a combustion appliance controller 60). In such an instance, the valve controller 26 may be configured to initiate and operate a VPS test and/or leakage test independent of an attached device and may be configured to disable a heat call or other signal to and/or from an attached device, when appropriate.
Those skilled in the art will recognize that the present disclosure may be manifested in a variety of forms other than the specific embodiments described and contemplated herein. Accordingly, departure in form and detail may be made without departing from the scope and spirit of the present disclosure as described in the appended claims.

## Claims

1. A valve assembly for controlling fuel flow to a combustion appliance, the valve assembly comprising:
a valve body having an inlet port and an outlet port, with a fluid path extending between the inlet port and the outlet port;
a first valve situated in the fluid path between the inlet port and the outlet port;
a second valve situated in the fluid path between the inlet port and the outlet port downstream of the first valve, with an intermediate volume between the first valve and the second valve defined by the valve body;
a first valve actuator, secured relative to the valve body, for selectively moving the first valve between a closed position, which closes the fluid path between the inlet port and the outlet port, and an open position;
a second valve actuator, secured relative to the valve body, for selectively moving the second valve between a closed position, which closes the fluid path between the inlet port and the outlet port, and an open position;
an intermediate pressure sensor in fluid communication with the intermediate volume between the first valve and the second valve for sensing a measure that is related to a pressure in the intermediate volume;
a controller operatively coupled to the first valve actuator, the second valve actuator and the intermediate pressure sensor, the controller programmed to:
close both the first valve via the first valve actuator and the second valve via the second valve actuator;
identify a measure related to an initial pressure in the intermediate volume of the valve body;
identify a predetermined fixed duration, wherein the predetermined fixed duration is stored in memory at the time of initial install of the valve assembly and is independent of the initial pressure;
determine a threshold value based at least in part on both the measure related to the initial pressure and the identified predetermined fixed duration;
identify a measure that is related to the pressure in the intermediate volume, and compare the identified measure related to the pressure in the intermediate volume during the predetermined fixed duration to the determined threshold value; and
output an alert signal if the measure related to the pressure in the intermediate volume during the predetermined fixed duration crosses the threshold value.

2. The valve assembly of claim 1, wherein the predetermined fixed duration is one of a test duration and a duration less than the test duration.

3. The valve assembly of claim 1, wherein the intermediate pressure sensor senses the measure related to the initial pressure before both the first valve and the second valve are closed, after both the first valve and the second valve are closed, or both.

4. The valve assembly of claim 1, wherein the valve assembly further includes an upstream pressure sensor situated upstream of the first valve, wherein the upstream pressure sensor identifies the measure related to initial pressure in the intermediate volume of the valve body before both the first valve and the second valve are closed, after both the first valve and the second valve are closed, or both.

5. The valve assembly of claim 1, wherein the threshold value is determined based at least in part on the measure related to the initial pressure in the intermediate volume of the valve body, the identified predetermined fixed duration, and an acceptable actual leakage rate value.

6. The valve assembly of claim 5, wherein the acceptable actual leakage rate value is adjustable from a first value to a second value in the field.

7. The valve assembly of claim 1, wherein the predetermined fixed duration is adjustable from a first value to a second value in the field.

8. The valve assembly of claim 1, wherein the controller is further configured to disable operation of the valve assembly in response to the alert signal.

9. The valve assembly of claim 8, wherein disabling operation of the valve assembly includes closing both the first valve and the second valve.

10. The valve assembly of claim 1, wherein the measure related to the initial pressure in the intermediate volume of the valve body is sensed by an upstream pressure sensor situated upstream of the first valve with one or more of the first valve and the second valve in the closed position.

11. The valve assembly of claim 1, wherein the measure related to the initial pressure in the intermediate volume of the valve body is sensed by the intermediate pressure sensor with the first valve in the open position and the second valve in the closed position.