Universal apparatus and method for configurably controlling a heating or cooling system

A system controller is provided that includes a communication network for transmitting and receiving information from an installed blower motor controller, and a removable memory device connected to the system controller. The removable memory device includes stored system parameter information related to a particular heating or cooling system, which information includes at least motor related parameters related to one or more types of blower motors. The system controller further includes a processor that receives, via the communication network, identifying information from the blower motor controller that identifies the type of blower motor that is installed. The processor is configured to retrieve motor related parameters corresponding to the specific identified blower motor from the memory device, and to send the corresponding motor related parameters to the blower motor controller.

FIELD

The present disclosure relates to heating and/or cooling systems, and more particularly to system controllers for controlling the operation of heating and/or cooling systems.

BACKGROUND

Manufacturers of heating and/or cooling systems typically design a number of different units to accommodate a variety of building sizes and needs. For example, a higher capacity multi-stage heating system may be required for a newly expanded building with an adequate cooling system, while an older building with a hydronic heating system may only require the installation of a replacement cooling system. Likewise, a newly constructed building may include an energy efficient heating and cooling system capable of operating at different stages or capacities, to operate at the required level of heating or cooling in an energy efficient manner. Accordingly, the various heating and cooling systems offered by manufacturers will each require a controller configured for the particular system.

SUMMARY

The present application discloses various embodiments of a universal system controller for controlling the operation of a heating and/or a cooling system. In one embodiment, a system controller is provided that includes a communication means for transmitting and receiving information from an installed blower motor controller, and a removable memory device connected to the system controller. The removable memory device includes system parameter information stored thereon that relates to the particular heating or cooling system, where the system parameter information includes at least motor related parameters relating to the operation of one or more types of blower motors. The system controller further includes a processor configured to receive via the communication means the communication of identifying information from the blower motor controller that identifies the type of blower motor installed in the system. The processor is configured to retrieve motor related parameters corresponding to the specific identified blower motor controller from the memory device, and to send said corresponding motor related parameters to the blower motor controller.

DETAILED DESCRIPTION

The present application describes various embodiments of a controller for controlling a number of different environmental control systems that include a blower motor and a blower motor controller. Some environmental control systems may only include a heat-only system, which may be operated independent from a separate cooling system. In this example, the heating system would require blower operation at a specific airflow or cubic feet per minute (CFM) for a heat and fan mode of operation. Other systems may include heating and cooling components and require blower operation at specific airflows/CFM levels for different capacity levels for a heat, cool and fan mode of operation. Either of the above systems could be sized to operate at different maximum capacities, and could have a different size blower drum or wheel. The system could also utilize different motors of various horsepower levels, for driving the blower to achieve a desired airflow (or CFM). Accordingly, achieving a desired CFM for a particular heating and/or cooling system would require a specific motor installed in the system to operate at a select speed (either clockwise or counter-clockwise as required) to drive the particular blower drum to produce the desired CFM. It should be understood that the above description of various heating and/or cooling systems are for illustrative in nature, and serve the purpose of demonstrating that heating and cooling units may include different blower designs sizes and capacities, which are operated at different levels depending on the type of system.

For the above reasons, systems typically employ a blower motor controller that utilizes coefficients and parameters specific to the particular blower and/or system, which are used in determining a speed for which the installed motor will achieve the requested airflow or CFM. Manufacturers may also design different capacity levels for a heating or cooling system. This may require each particular system type or capacity level to be controlled at different airflow CFM's. Accordingly, the system controller for each particular size and type of system must be configured for controlling and/or specifying the various blower CFM levels required for the particular system, and the various coefficients and parameters specific to the particular blower/blower motor installed in the system.

Thus, each particular heating and/or cooling system requires a particular controller that is specific to that particular size and type of system. It should be understood that while a motor may be installed and configured to operate in various different blowers/systems, the present application discloses various embodiments of a universal controller that may be installed and configured to control and operate a variety of different heating and/or cooling systems.

In the various embodiments disclosed in the present application, a universal configurable controller is provided, which permits manufacturers of heating and/or cooling systems to configure a “blank” controller for each particular size and type of system. In the event that the universal controller (once installed and configured) becomes damaged, defective, or requires replacement for any reason, the universal controller if configured such that it may be readily replaced by a “blank” universal controller, as will be described below.

The various embodiments of a controller include a communication means, such as a Universal Asynchronous Serial Port (UART), a 4-wire connection, or other forms of communication lines, through which information is communicated between the controller and a blower motor controller associated with the particular installed blower motor. The various embodiments of a controller further provide for input of information to the controller, and a memory associated with the controller. The various controller embodiments further include a processor that, upon installation and power up of the controller, is configured to receive the input of information that includes parameters associated with the particular system and its installed blower motor, which information is stored in the memory associated with the controller. The processor is further configured to receive information from the blower motor controller identifying the manufacturer identification and/or horsepower of the installed motor. From this identifying information, the processor is configured to retrieve from memory the motor related parameters that are specific to the identified blower motor, and to send the specific parameters to the blower motor controller. The motor related parameters are sent to the blower motor controller, to thereby provide the specific operating parameters for the particular system and the identified blower motor to the blower motor controller, which subsequently uses the parameters in controlling the operation of the blower motor.

Accordingly, one or more embodiments of a universal system controller are disclosed, which comprise a communication means for transmitting and receiving information from an installed blower motor controller, and a removable memory device connected to the system controller. The removable memory device includes system parameter information stored thereon that relates to the particular heating or cooling system, where the system parameter information includes at least motor related parameters relating to the operation of one or more types of blower motors. The system controller further includes a processor configured to receive via the communication means the communication of identifying information from the blower motor controller that identifies the type of blower motor installed in the system. The processor is configured to retrieve motor related parameters corresponding to the specific identified blower motor controller from the memory device, and to send said corresponding motor related parameters to the blower motor controller. The system controller thereby provides the specific operating parameters corresponding to the identified blower motor to the blower motor controller, for use in controlling operation of the blower motor.

According to one aspect of the present disclosure, one embodiment of a universal configurable controller100is shown inFIG. 1. The controller100includes a memory102associated with the controller100that is initially “blank”, or absent any parameters specific to any particular system or blower motor. The memory102associated with the controller100is preferably a programmable non-volatile memory device, having an electrically erasable programmable read only memory (EEPROM). The memory102could be external to the controller's processor, or it could be embodied as an on-board memory associated with a processor.

The controller100may include an input interface104that allows manufacturers who purchase the controller100to input information including parameters specific to a particular heating and/or cooling system that the manufacturer is producing. The input interface104permits the input of information that includes parameters specific to a number of various blower motors that may be installed, including the particular blower motor installed in the particular system. This permits manufacturers to configure the “blank” controller100for a particular size and type of system, which includes a particular blower operated by any one of a number of specific motor types. The memory102associated with the controller100is preferably utilized to store this input information.

The first embodiment of a controller100includes a communication means106, such as a Universal Asynchronous Serial Port (UART)106that provides a predetermined baud rate serial bit stream signal. The communication means may alternatively comprise a 4-wire BUS connection, or any other forms of connection for suitably permitting communication of signal information. The communication means106preferably communicates a signal that includes data or information provided by a data port of a processor or microprocessor of the controller100. The communication means106is connected or configured to provide for communication of information between the controller100and a blower motor controller150associated with a particular installed blower motor160.

The first embodiment of a controller100further includes a processor108, which can be a microprocessor, a microcontroller, a digital signal processor (DSP) or any other suitable processing device. Upon application of electrical power to the controller100, the processor108is configured to receive via the input interface104an input of information that includes parameters associated with a variety of blower motors160that may be installed for the particular system. This information is preferably input by a manufacturer of heating or cooling systems, and may include various parameters associated with each type of particular motor that the manufacturer has selected or identified as a motor that may be installed for the particular size and type of system. The specific information is preferably input via the input interface104to the controller100by the manufacturer at the time of manufacture of the particular system, and is stored in the memory102associated with the controller100.

The processor108is further configured to receive information from the blower motor controller150via the communication means106, which information identifies the manufacturer identification and/or horsepower of the blower motor160that is actually installed in the heating/cooling system of the manufacturer. From this identifying information, the processor108is configured to retrieve from memory102motor related parameters that are specific to the identified blower motor160, and to send the specific parameters to the blower motor controller150.

Once the controller100is selected or designated for a particular heating and/or cooling system, and the processor108preferably receives data or information that is input by the manufacturer via the interface device104. The system controller100would then be configured by the manufacturer for the particular heating or cooling system. The processor108stores the specific values and parameters into the memory102, such that the information and/or parameters relating to the particular blower motor that is installed can be retrieved and used for controlling operation of the identified blower motor. The processor108can then send the appropriate stored configuration variables or values to the blower motor controller150via the communication means106.

In view of the above, the controller100is thereby configured to provide the specific operating parameters corresponding to the particular system and the identified blower motor160to the blower motor controller150, for subsequent use in controlling the operation of the blower motor160. The controller100may further include a separate memory module110that is connected to the controller100via a Universal Serial Bus (USB) interface, or other comparable connection means. The processor108is further configured to communicate the information input by the manufacturer to the memory module110, such that the system specific information is stored on the memory module. In the event that the controller100becomes damaged, defective, or requires replacement for any reason, a replacement controller that is “blank” may be used to replace the originally installed controller, where the memory module110is simply removed from the original controller and reconnected to the replacement controller. Accordingly, a universal “blank” configurable controller is provided that permits manufacturers of heating and/or cooling systems to configure the “blank” controller for a particular size and type of system, while also permitting the replacement of the installed configured controller with a “blank” replacement controller.

When a “blank” system controller is first supplied to a manufacturer or OEM, the OEM programs it for the specific unit it will be installed in. After the system controller is programmed or configured by the manufacturer, a “blank” separate memory module is installed via the USB interface on the controller. When the controller detects the installation of the blank memory module, it copies the OEM information that was stored in the controller's on-board memory102to the separate memory module110. The controller100is configured to synchronize the onboard memory with the separate memory module110.

As stated above, the controller100is configured to receive a plurality of input signals. The system controller100includes an input interface104that is configured to receive from the system manufacturer the input of a number of parameters that may be used to control the operation of the heating or cooling system the blower motor controller. The manufacturer preferably connects a device to the input interface104that provides motor related data in the input signals into the controller100. The information preferably includes motor related parameters corresponding to a number of different blower motors or blower motor controllers.

As stated above, the system controller100may receive input information including various coefficients and parameters, and communicate information to the blower motor controller that includes one or more coefficients and parameters. For example, the processor108may communicate a command signal to the motor controller that identifies the Message type, packet number and length of information, as well as specific information such as that shown in the table below.

TABLE 1Destination or profileCodeDescriptionOEM ID12White-RodgersManufacturer ID9OEM customerNode/Control type3C2Number of fields4data to be extractedSystem configuration ID2Indoor blower run mode2Cubic feet per minute modeIndoor blower max speed1400Max Cubic feet per minuteBlower cutback slope16Blower cutback speed255Heat on delay45secondsCool air flow multiplier (0)100Percent of maximumCool air flow multiplier (1)90Percent of maximumCool air flow multiplier (2)80Percent of maximumHeat air flow multiplier (0)100Percent of maximumHeat air flow multiplier (1)90Percent of maximumHeat air flow multiplier (2)80Percent of maximum

The system controller100may be configured to communicate a signal to the motor controller that includes one of the above parameters, which signal is transmitted according to a specific communication protocol. One such protocol is the ClimateTalk protocol developed by Emerson Electric Co., which is disclosed in U.S. application Ser. No. 12/107,747, filed Apr. 22, 2008, which is incorporated herein by reference. This protocol specifies how information is identified and recognized by the system controller, such as the parameters associated with one or more specific motor types that may be input to the system controller. The table below illustrates a portion of this protocol relating to a blower motor, as an example.

Each of the parameters that are required by the motor controller may be communicated between the system controller and the motor controller in accordance with the above protocol, and may be transmitted by a particular message packet structure, such as that described in section 5.5 of the ClimateTalk protocol disclosed in application Ser. No. 12/107,747. Such a transmission protocol could be used to transmit a signal to the motor controller indicating the requested mode of operation, such as a CFM mode, as indicated in the signal below. The Data Payload specifies a Mode of 0 for speed mode, 1 for Torque mode, and 2 for Airflow mode.

Similarly, the above structure could also be used to communicate a maximum CFM setting, and other parameters required by the motor controller. Accordingly, the system controller100may be configured to request the operation of the blower motor at a particular airflow in terms of cubic feet per minute (CFM), by communicating command signals to the blower motor controller, where the command signals include embedded therein the requested CFM and parameter information that is specific to the identified blower motor. The blower motor controller would utilize the above mode in determining the speed for establishing blower motor operation at the requested CFM.

As noted above, the number of terms and values employed in the configuration variables, such as the values of the predetermined coefficients, are typically determined based on the particular HVAC system in which the interface device104will be used. In this manner, the controller100can be configured for one or more particular heating or cooling systems via the information stored in the memory102. In many cases, this will eliminate any need to store parameter data in the blower motor controller. As a result, a universal “blank” system controller can be used with a wide variety of blower motors in a number of different heating and/or cooling systems. For example, a particular ½ horsepower blower motor, with the appropriate motor related parameters, can be used in a number of different heating and/or cooling systems requiring up to a ½ horsepower blower motor, where the universal configurable controller is configured to include the parameters that are specific to the particular motor. This is in contrast to, for example, using multiple different HVAC system controllers for each different ½ horsepower blower motor, where each controller is programmed for a different type of HVAC system. Accordingly, a generic configurable system controller may be used in a number of different HVAC systems having different blower motor controllers, by configuring the controller with the motor related parameters specific to the particular blower motor controller that is installed.

When the system controller100is configured by the manufacturer for a specific HVAC unit it will be installed in, the HVAC unit and system controller may be shipped to an installation site, and installed at the site. An HVAC contractor may at such time change some of the parameters of the system at the time of installation, to “tweak” the parameters by adjusting the trim, CFM, ramp rate, heat delay, or other settings to accommodate the actual installation requirements. As these values are entered, the system controller100saves the information to the memory102, and also the separate memory module110. In this manner, all information after installation is in effect duplicated in both memory locations.

If the system controller fails, a “blank” or generic replacement controller may be installed in its place. The separate memory module may be removed from the failed controller and may be connected via the USB interface onto the replacement controller. The replacement controller then synchronizes its memory with the memory module, but in this instance it copies all system and site specific information from the separate memory module to the on-board memory102of the replacement controller100.

Referring toFIG. 2, a method for configuring a system controller for a heating or cooling system is shown. The input signals received at step200may be any type of signals useful in determining an appropriate blower motor and/or air flow configuration for the HVAC system. In some embodiments, these input signals include both configuration input signals and motor operating parameter inputs.

The configuration input signals are signals relating to configuration settings typically made in the field by an operator during installation of the HVAC system. These settings may be input at the time of manufacture or the time of installation. For example, the value of a particular configuration input signal may indicate the type or size of a particular component employed in the HVAC system, such as the tonnage of an outdoor compressor unit. In contrast, the motor operating input signals are signals that change during normal operation of the HVAC system. For example, the value of a particular operating input signal may represent a call for heat or cool operation. The operating input signals are typically provided by a system controller, and may include operating signals received by the system controller from a thermostat. The controller stores the information into a memory associated with the controller100.

After installation and power-up in steps202,204, the controller100is configured to establish communication at step206. The controller then receives the communication of information identifying the motor manufacturer or type of blower motor at step208. Based on this identifying information, the controller100is configured to communicate at step212those parameters that correspond to the specific installed blower motor160to the motor controller150. It should be understood that the controller100may request operation of the blower motor controller150to establish a particular CFM of airflow, by communicating a command signal that may have embedded therein the input information of a coefficient or operating parameter, which is used by the motor controller150in determining a speed for the blower motor. The controller100may communicate one or more command signals, each having embedded therein information that is specific to the particular blower motor that is installed, whereupon receiving each of the required parameters or inputs the motor controller160is configured to operate the motor to achieve the desired CFM. Configuration input signals may also be provided to the system controller, particularly where the system controller includes switches or other input means for a technician to make configuration settings in the field. As will be apparent to those skilled in the art, a number of configuration input signals and/or operating signal inputs employed in any given system or application.

Referring toFIG. 3, a second embodiment of a single configurable controller300is shown. The controller300includes a memory302associated with the controller300that is initially “blank”, or absent any parameters specific to a particular system or blower motor. The controller300further includes a connector304for receiving a separate memory module310which is preferably connected to the controller300via a Universal Serial Bus (USB) interface connector, or other comparable connection means. The separate memory module310allows manufacturers of a particular heating and/or cooling system to store thereon information pertaining to the particular system, including parameters specific to a number of blower motors that may be installed for the particular system or blower. This permits manufacturers to configure the “blank” controller100for a particular size and type of system.

The second embodiment of a controller300includes a communication means306, such as a Universal Asynchronous Serial Port (UART)306that provides a predetermined baud rate serial bit stream signal, or a 4-wire connection, or other forms of connection for permitting communication. The communication means306preferably communicates a signal including information communicated via a data port of a processor308(or microprocessor) of the controller300. Through the communication means306, information is communicated between the controller300and a blower motor controller350associated with a particular installed blower motor360. The memory module310permits the controller to download or retrieve stored information that includes parameters specific to a number of various blower motors that may be installed, including the particular blower motor installed in the particular system. The controller310preferably stores the retrieved information on an internal memory (not shown) that is associated with the controller300.

The second embodiment of a controller300further includes a processor308that, upon application of electrical power to the controller310, is configured to retrieve the stored information from the memory module310, which information includes parameters associated with a variety of blower motors360that may be installed for the particular system. This information may include various parameters associated with each type of particular motor that the manufacturer has selected or identified as a motor that may be installed for the particular size and type of system. The specific information is preferably stored on the memory module310by the manufacturer at the time of manufacture of the particular system.

The processor308is further configured to receive information from the blower motor controller350, which information identifies the manufacturer identification and/or horsepower of the actual installed motor360. From this identification information, the processor308is configured to retrieve from memory302motor related parameters that are specific to the identified blower motor360, and to send the specific parameters to the blower motor controller350. The controller300thereby is configured to provide the specific operating parameters corresponding to the particular system and the identified blower motor360to the blower motor controller350, for subsequent use in controlling the operation of the blower motor360.

Referring toFIG. 3, the controller may further be configured to communicate via the communication means to other controllers in the environmental control system, such as a Unitary Controller370for an Air Conditioning system380. The controller370may provide control signals or information to a compressor380or fan motor384for the Air Conditioning system. Accordingly, the system controller300may further be configured to communicate to a Unitary Air Conditioning Unit controller370for controlling one or motors of an Air Conditioning system similar to the manner that is described above.

In a third embodiment of a system controller for a particular HVAC system having at least one other controller as inFIG. 3, the system controller is in communication with the at least one other controller via the communication means306. Unlike the HVAC system shown inFIG. 1in which a separate memory module110is necessitated to provide for back-up of system specific parameters stored in the memory102of the sole system controller100, the HVAC system inFIG. 3includes at least one other system controller370having an on-board memory372. Accordingly, for the system controller300shown inFIG. 3, the system controller does not require a separate memory module for storing a back-up of parameters, but instead relies on the memory372in the Unitary Air Conditioning Unit controller370.

For example, where the controller300is selected or designated for the particular heating and/or cooling system shown inFIG. 3, the manufacturer may input via an interface device304system specific information to configure the controller300for the particular heating or cooling system. The system control300has a processor308that stores the specific values and parameters into its memory302, such that the information and/or parameters relating to the particular blower motor that is installed can be retrieved for controlling operation of the identified blower motor. The processor308could then receive information from the blower motor controller350via the communication means306, which identifies the manufacturer identification and/or horsepower of the installed blower motor360. From this identifying information, the processor308would retrieve from memory302motor related parameters that are specific to the identified blower motor360, and send the specific parameters to the blower motor controller350. The processor308can communicate the specific parameters, configuration settings, variables or values to the blower motor controller350via the communication means306. Once the system controller has save the parameters specific to the particular system in the local memory302of the system controller300, the system controller300is also configured to communicate the system specific parameter information (via communication means306) to the Unitary Air Conditioning Unit controller370, which would store the system parameter information in its on-board memory372.

In the event that the controller300becomes damaged, defective, or requires replacement for any reason, a replacement “blank” configurable controller may be used to replace the originally installed controller. The system controller's onboard memory302is typically the dominant memory, unless the system controller is replaced with a “blank” replacement controller. If the system controller302is a “blank” replacement controller, the on-board memory372of the Unitary Air Conditioning Unit controller370becomes dominant. This may be established, for example, by the presence of a default code on a blank controller that signals the controller's processor that it is not dominant. Once the system controller300communicates a request to the the system controller300stores in its local memory the parameters that were stored in the memory372of the Unitary Air Conditioning Unit controller370. The replacement system controller300is configured to store this information on its onboard memory302, such that the default code is over-written and the controller's processor no longer detects the code. At this point, the replacement system controller300would recognized the local memory302as being dominant once again. As such, the processor308of the replacement controller300is configured to establish the on-board memory302as the dominant memory. Where a “blank” replacement controller302is installed in place of the original dominant controller, the default code on the blank replacement controller would signal the replacement controller's processor that it is not dominant, and the processor would retrieve information from the on-board memory372of the Unitary Air Conditioning Unit controller370. This back-up of parameter information would be stored in the on-board memory302of the replacement system controller300. Accordingly, a single “blank” configurable controller is provided that permits manufacturers of heating and/or cooling systems to configure the “blank” controller for a particular size and type of system, while also permitting the replacement of the installed configured controller with a “blank” replacement controller.

In the above embodiments, the system controller further includes a synchronizing aspect with regard to the two memory locations. For example, the on-board memory102of controller100and the separate memory module110have a particular synchronization priority, which is a function of which memory is dominant. The system controller's onboard memory102is always the dominant memory, unless the system controller is replaced with a “blank” replacement controller, in which case the memory module110becomes dominant until it has updated the onboard memory of the replacement controller, at which point the system memory102becomes dominant once again. This may be established, for example, by the presence of a default code on a blank controller that signals the controller's processor that it is not dominant. Once the controller is programmed or configured by a manufacturer for a particular HVAC system, the default code is over-written and the controller's processor no longer detects the code. As such, the processor establishes the on-board memory102as the dominant memory. If a “blank” replacement controller102were installed in place of the dominant controller, the default code on the blank replacement controller would signal the controller's processor that it is not dominant, and the processor would retrieve information from the separate memory module and store the information on the on-board memory102.

According to another aspect of the present application, various embodiments of a method for controlling the operation of a system controller for a heating or cooling system are provided. Referring toFIG. 4, one embodiment of a method for controlling a system that includes a system controller and a blower motor controller is disclosed. The method comprises the step404of applying electrical power to the heating or cooling system, the system controller and the blower motor controller, and establishing communication via a bus network between the system controller and the blower motor controller at step406. The method further comprises the step408of receiving from the blower motor controller information identifying the particular blower motor controller via the bus network, and retrieving from memory the specific motor related parameters corresponding to the identified blower motor controller at step410. The system controller then sends the specific motor related parameters corresponding to the identified blower motor controller to the blower motor controller at step412, thereby provide the operating parameters specific to the identified blower motor controller, which are then utilized in controlling the operation of the blower motor.

In another aspect of the present application, the controllers may also be configured to store component controller information in the memories of other controllers in the HVAC system. For example, the separate memory module110used with the system controller100may also include system parameters for an inducer motor controller or an air conditioning motor controller. If either of these other types of controllers become damaged, the replacement controllers for these components could detect the presence of a communication network, and request the system controller100to communicate the parameters for the particular unit to the particular device, such as the inducer motor controller or air conditioning fan motor controller.

In another aspect of the present application, the above embodiments may further include an alternate configuration as well. In the above embodiments, the system controller may further be configured to receive communication of information relating to other operating parameters of the heating or cooling system. For example, the processor308may be coupled to an input means or the communication means306, and may be configured to determine an appropriate system configuration for a given combination of input signals received at the input connector306from the memory device304. Although the embodiment ofFIG. 3may employ an input means and/or a wired communication means306, it should be understood that one or more wireless inputs and/or wireless outputs (i.e., without connectors) can be used in a given application of the present disclosure. As shown inFIG. 3, the heating and cooling system controller300, a blower motor controller350( for controlling an electric motor360and a blower), and a thermostat390. The controller300may further comprise an interface connector (not shown) that includes sixteen input pins for receiving input signals to the system controller300via a sixteen wire communication cable (not shown). The types of signals provided at the pins of the input connector304in this particular HVAC system are indicated in Table 2, below.

The C1and C2pins are used for ground connections; the W/W1signal represents a call for low heat signal; the DELAY signal represents the amount of time the blower motor assembly406should delay start-up when heating/cooling operation is commenced, or delay shut-down after heating/operation is concluded; the COOL signal represents one or more cooling operation configurations; the Y1signal represents a call for low cooling signal; the ADJUST signal represents a trim control signal for adjusting circulator speed, based on conditions such as humidity, etc; the Out− signal (together with the Out+ signal) represent a signal for flashing or pulsing an LED in a manner that is indicative of the motor's speed; the O signal represents the presence of a refrigerant reversing valve in a heat pump system that would affect the circulator blower speed; the BK/PWM signal represents a signal indicating the presence of a humidifier, for fractionally adjusting the speed based on humidifier operation; the HEAT signal represents one or more heating operation configurations; the R signal represents the presence of a low-voltage HVAC transformer; the EM/W2signal represents a call for high heating signal; the Y/Y2signal represents a call for high cooling signal; the G signal represents a signal for requesting circulator blower operation, and the Out+ signal (together with the Out− signal) represent a signal for flashing or pulsing an LED in a manner that is indicative of the motor's speed.

In this particular embodiment, each of the following input signals correspond to one or more variables in the airflow equation: HEAT, COOL, ADJUST, W/W1, Y1, O, BK, R, EM/W2, Y/Y2and G. Of these, the following input signals are configuration signals relating to configuration settings made during installation or startup of the HVAC system400: HEAT, COOL, DELAY and ADJUST. The following other signals are operating input signals that change during normal operation of the HVAC system: W/W1, Y1, O, BK, R, EM/W2, Y/Y2and G. The following operating input signals are generated by the thermostat390and provided to the interface device204via the system controller390typically as alternating or pulse width modulated (PWM) signals: BK/PWM. The system controller300may be configured to use lookup tables, for example, for selecting and retrieving specific parameters from the controller's memory302in response to user input signals from the thermostat390, to thereby provide the necessary information to the blower motor controller or other components to control the operation of the particular system in response to the thermostat390.

In the embodiment ofFIG. 3, the DELAY signal does not correspond to any particular variable in the airflow equation. Instead, the DELAY signal indicates the amount of time that the blower motor assembly406should delay start-up after a call for heating/cooling has been called for, or continue to operate after a call for heat or cooling has ended. This delay time is communicated to the blower motor controller350together with the coefficients and parameters from Table1above, to thereby control the operation of the blower motor. Accordingly, the system controller300may further control other operational aspects of the blower and other components, which may be specific to the particular heating or cooling system.

It will be understood by those skilled in the art that the above system controller may be employed with either a cooling or heating system without implementing the other, particularly if the thermostat is used or designed to control only a cooling or a heating system. It will be understood that the system controller described above may be utilized in forms of heating and cooling systems, including multistage or variable speed heating and cooling systems. Accordingly, it should be understood that the disclosed embodiments, and variations thereof, may be employed in any type of heating system.