Patent ID: 12241640

DETAILED DESCRIPTION

As described hereinabove, tankless water heaters heat a cold water flowed into the tankless water heater inlet and provide an on demand heated water from the tankless water heater outlet. One common tankless water heater preventive maintenance is to flow a mild acid such as a food grade vinegar through the internal pipes and heat exchanger to prevent buildup of deposits that could degraded efficiency of the tankless water heater, or even cause a system failure. However, it is important to not introduce the cleaning solution into the water system, typically a potable water system including home hot water systems. Therefore, isolation valve assemblies are provided which allow for the tankless water heater inlet and outlets to be isolated from the cold water feed and hot water supply lines during cleaning operations.

One problem with existing isolation valves for tankless water heaters is that a right hand or left hand physical configuration is fixed at time of manufacture. Such fixed structures mean either plumbing for a given right hand or left hand structure or buying particular isolation valves with a needed right hand or left hand physical configuration of ports and valves.

Therefore, there is a need for reconfigurable, swappable, or reversible isolation valves for tankless water heaters.

Also, as part of the solutions, a relatively compact isolation valve for tankless water heaters was realized, in part, by introduction of a plug type valve. With the symmetry achieved by the plug type valve, it was realized that opposing ports (e.g. threaded ports) can be introduced on either side of a new type of compact isolation valve for tankless water heaters. Either side port can be used for the purge valve/purge port part, the different opposing port either capped by a threaded plug, or available as an option port, such as for an optional sensor, such as a temperature sensor.

FIG.1is a drawing showing an exploded view of a new plug type isolation valve according to the Application.FIG.1shows an exemplary isolation valve100typically used with tankless water heaters. Isolation valve100is shown configured with a pressure relief valve141for the hot water side of a tankless water heater. A same new type cold water isolation valve according to the Application (not shown inFIG.1) can omit the pressure relief valve, and can also entirely omit the high pressure relief port. Continuing withFIG.1, a hot water side isolation valve100includes four ports in one valve body. Port193is adapted to fluidly couple (typically by an intervening pipe) to the hot water outlet of the tankless water heater. Water distribution system port198is adapted to fluidly couple to a pipe of a hot water distribution system of a home or building. Port196is fluidly coupled to a drain assembly121which includes a second on/off valve125controlled by handle123. Port195fluidly couples to the pressure relief valve141for the hot water isolation valve type.

In normal operation, isolation valve handle103is set so that hot water flows normally out of a tankless water heater through the isolation valve100and into the home or building hot water distribution system. In a drain operation, typically for testing or cleaning the tankless water heater, isolation valve handle103is turned 90° from the normal operation position to the drain position. In a drain operation, port198to the hot water distribution system of the home or building is closed.

Because of the new use of a plug valve, one aspect of what is new is that there is always water fluidly coupled to port196, the fluid connection to the drain assembly121, in both the normal operation and in the drain operation. One advantage of this new approach is that the drain assembly, with its own on/off valve125, can also be used for diagnostic testing during normal water heater operation without inconveniencing hot water users in the home or building. Another advantage is that plug valve assembly102is relatively simple compared to more complex valves which open the normal hot water path, while closing the fluid path to the drain port. A plug valve can also be less complicated and less costly to manufacture than a ball valve of the prior art, at least in part, because the relatively large machined metallic ball is no longer required.

Another feature of the new isolation valve is that is reversible for convenient installation, where instead of some specific pipe paths appropriate to a right hand configuration or a left hand configuration, either of a left side port196, or a right side port197can accept the drain assembly121, while a plug165can be installed in the non-used side.FIG.1shows a right hand configuration, where in a typical installation below a tankless water heater, isolation valve handle103will be on the right side, with the drain assembly pointed outward from the tankless water heater installation (typically outward from a wall on which the tankless water is mounted) (SeeFIG.5D).

Another feature of the new reversible plug valve based isolation valve100, is that during a drain operation, the unused port (port196or port197) can be used to accept an option sensor, such as, for example an option temperature sensor or pressure sensor. The extra port of the isolation valve100is particularly useful for factory testing, such as factory R&D work, and post production testing operations. However, there can also be diagnostic sensor uses during a drain operation for a tankless water heater installed in the field. While the unused port (port196or port197) is blocked during normal operation, the unused port can still be used for a temperature sensor which does not extend all the way into the path of the rotating plug seal of the plug valve. The shallow mount temperature sensor can be used to measure the temperature of the unitary metallic isolation valve body190(typically brass, however any suitable metallic material can be used) of the isolation valve100during normal operation, a temperature, accounting for radiative loss to the ambient equipment room or basement temperature, indicative of the hot water temperature and hot water flow rate. An isolation valve body190can also be manufactured of any suitable non-metallic body as well, however then, the temperature sensor would only be most useful when directly exposed to the fluid flow when the plug is blocking port198and the unused port (196or197) is fluidly coupled to the fluid flow.

An additional feature of the new reversible plug valve based isolation valve100, is that the ports195,196,197are located on a single plane. In other words, the flow paths through the ports195,196,197intersect. Placing the ports195,196,197on a single plane allows the valve100to have a shorter height and more easily fit within a compact space when installed on a tankless water heater. In the exemplary embodiment shown, the drain ports196,197are each located ninety degrees from the pressure relief port195. In other words the flow paths through the ports196,197are perpendicular to the flow path through the port195.

Continuing withFIG.1, the new isolation valve100of the Application is described in detail beginning with a table of components for convenient reference.

TABLE OR REFERENCE DESIGNATORS FOR FIG.1

100ISOLATION VALVE101isolation valve plug102plug valve ASSEMBLY103isolation valve handle104plug seal105isolation valve handle mounting screw107plug valve stem109reversible handle stop111aright side normal operation stop post111bleft side normal operation stop post113plug end seal115spring clip117spring slot121drain ASSEMBLY123drain valve handle125drain valve127drain cap131tankless water heater connection ASSEMBLY133compression nut135compression insert137compression port seal141pressure relief valve ASSEMBLY163unused port seal (sensor port)165unused port plug190isolation valve body191plug valve port193tankless water heater port (hot water,FIG.1)195pressure relief port196right hand isolation reversible port197left hand isolation reversible port198water distribution system port (hot water,FIG.1)

Plug valve—Plug valve assembly102makes possible the feature of the isolation valve100where the drain assembly is always available for use during both normal and drain operations. As shown inFIG.1, in normal operation, plug valve assembly102as controlled by isolation valve handle103positions plug seal104over the unused port, thus opening a normal operation flow path between the tankless water heater (port193) and the hot water distribution system port (port198), thus providing a normal flow of hot water from tankless water heater to the home or building.

In a drain operation, in the right hand configuration ofFIG.1, isolation valve handle103is rotated 90° towards the direction of the drain assembly (typically away from the wall, pointing into the room space, handle about parallel to the long axis of the drain assembly). Now, the plug seal rotates to cover and close the hot water distribution system port198.

The drain assembly121is always conveniently coupled to the tankless water heater, where the drain assembly121includes its own on/off drain valve125. Thus, particularly during factory R&D or post production testing, there can be diagnostic equipment fluidly coupled to a normally operating tankless water heater by opening drain valve125during normal operation (or, during a drain operation).

The reversible nature of isolation valve100is set to a right hand configuration or a left hand configuration by interchanging (reversing or swapping) the drain assembly121and the unused port plug between port196and port197. The plug valve assembly102is always present in port191. However, for the handle to turn outward towards the direction of the of the drain assembly121, reversible handle stop109can be flipped over 180° and reinstalled under isolation valve handle103so as to stop either against the right side normal operation stop post111a, or the left side normal operation stop post111b.

Isolation valve plug101provides the plug valve frame for rotating plug seal104which rotates 90° with rotation of the isolation valve handle. Plug end seal113can be any suitable plug valve end seal, typically an O-ring seal as shown inFIG.1.

The plug valve assembly can be mounted in to the isolation valve body190by any suitable mounting means, such as, for example, by threaded nut, or by spring clip115and spring slots117as shown inFIG.1. A retaining ring is another suitable method of assembling a plug valve (rotor) into the isolation valve body.

The drain assembly121includes an on/off drain valve125which is controlled by drain valve handle123. Drain cap127can be a dust cover, such as, for example a plastic dust cap to keep the drain end clear of foreign debris and protect any machine threads. Or, drain cap127can be a threaded metal cap with an additional sealing washer or ring to provide a second level of drain closure in addition to drain valve125. Drain assembly121can be installed in either of port196or port197, typically by any suitable connection, such as, for example, a threaded mechanical connection. For example, drain assembly121can include outer male threads and ports196,197, corresponding female machine threads. Any suitable mechanical coupling can be used. Typically, the drain assembly121is removable so that the drain assembly can be reversed between either of ports196,197, however, especially because such isolation valves are typically only installed once, and are typically not reused, or re-configured during the normal lifetime of the isolation valve, the drain assembly121can be supplied uninstalled with a one time non-removable mechanical coupling means to either of ports196,197, such as by a one-time mechanical mechanism (e.g. a onetime captive snap lock), and/or adhesive or glue connection. More typically, ports196,197are threaded ports which may or may not include an additional threaded sealing compound (e.g. a threaded sealing compound suitable for use with potable water). Most commonly, the drain assembly121and unused port plug165can be reversed in the field, both at the time of installation, and later if a system is re-configured, or in the less likely event that the isolation valve is re-used for another installation.

Tankless water heater port131can be fluidly coupled to the tankless water heater by any suitable means. For example, compression nut133, compression insert135, and compression port seal137ofFIG.1can be used to fluidly couple the isolation valve100to a tankless water heater hot water outlet via a relatively short length of pipe. Any suitable connection can be used, including, for example a flange mount to a tankless water heater.

An isolation valve100can be provided as an individual isolation valve part. More typically isolation valves are sold in pairs, one for the tankless water heater hot water outlet (e.g.FIG.1) and one for the cold water side without the high pressure relief valve, where the high pressure relief valve is typically only required on the hot water side. Or, such isolation valves100can be supplied with, or supplied already mounted to and fluidly coupled to the hot water outlet and cold water inlet of a tankless water heater.

FIG.2AthroughFIG.5Fshow various views of an exemplary hot water side isolation valve100in left hand and right hand configurations, in both a normal operation open position and a drain operation closed position. Here, open refers to the normal open path from the hot water outlet of the tankless water heater to the building hot water distribution system, and closed refers to the drain operation, where the normal open path from the hot water outlet of the tankless water heater to the building hot water distribution system is closed (shut off). The convention of left hand and right hand labels are used assuming the isolation valves are commonly installed underneath the tankless water heater. However, there is no such mounting requirement, and those skilled in the art will recognize that there may be applications where a right side installation is defined by the isolation valve handle mounted on the right side as one faces the tankless water heater typically mounted on a wall, or in other less common mounting applications, the isolation valve handle may be up, down, or left in a “right hand” isolation valve configuration. In other words is only important that the drain valve is reversable between ports196,197, and that the isolation valve handle103can be installed for any convenient 90° rotation by choice of installation size and rotatable position of rotatable handle stop109within the isolation valve handle103and with respect to the right side normal operation stop post111a, or the left side normal operation stop post111b.

Now, using the convention of the isolation valve mounted in the most common manner underneath a tankless water heater mounted to a wall,

FIG.2Ais a drawing showing top view of an isolation valve100in a left hand configuration, in the closed position.FIG.2Bis a drawing showing back view of the isolation valve ofFIG.2A.FIG.2Cis a drawing showing another back view of the isolation valve ofFIG.2Awith section line AA.FIG.2Dis a drawing showing an isometric view of the isolation valve ofFIG.2A.FIG.2Eis a cut away drawing of the isolation valve ofFIG.2A.FIG.2Fis a cut away drawing of the isolation valve ofFIG.2Aalong section line AA.

FIG.3Ais a drawing showing top view of an isolation valve100in a left hand configuration, in the open position.FIG.3Bis a drawing showing back view of the isolation valve ofFIG.3A.FIG.3Cis a drawing showing another back view of the isolation valve ofFIG.3Awith section line BB.FIG.3Dis a drawing showing an isometric view of the isolation valve ofFIG.3A.FIG.3Eis a cut away drawing of the isolation valve ofFIG.3A.FIG.3Fis a cut away drawing of the isolation valve ofFIG.3Aalong section line BB.

FIG.4Ais a drawing showing top view of an isolation valve100in a right hand configuration, in the closed position.FIG.4Bis a drawing showing front view of the isolation valve ofFIG.4A.FIG.4Cis a drawing showing another front view of the isolation valve ofFIG.4Awith section line CC.FIG.4Dis a drawing showing an isometric view of the isolation valve ofFIG.4A.FIG.4Eis a cut away drawing of the isolation valve ofFIG.4A.FIG.4Fis a cut away drawing of the isolation valve ofFIG.4Aalong section line CC.

FIG.5Ais a drawing showing top view of an isolation valve100in a right hand configuration, in the open position.FIG.5Bis a drawing showing front view of the isolation valve ofFIG.5A.FIG.5Cis a drawing showing another front view of the isolation valve ofFIG.5Awith section line DD.FIG.5Dis a drawing showing an isometric view of the isolation valve ofFIG.5A.FIG.5Eis a cut away drawing of the isolation valve ofFIG.5A.FIG.5Fis a cut away drawing of the isolation valve ofFIG.5Aalong section line DD.

Isolation valves according to the Application can use threaded connections. Any suitable threaded, compression, or soldered connections can be used.

Swappable Isolation Valve—FIG.6Ais a drawing illustrating how a right hand TWH isolation valve can be transitioned to a left hand TWH isolation valve;

FIG.6AandFIG.6Bare drawings that illustrate how a right hand TWH isolation valve can be transitioned to a left hand TWH isolation valve.FIG.6Bis a drawing showing the transitioned right hand TWH isolation valve ofFIG.6Aas a left hand TWH isolation valve. A swappable, or reversible isolation valve is shown as a right hand TWH hot water isolation valve710, transitioned or re-configured as shown by arrow799to a left hand TWH hot water isolation valve720. Similarly, the left hand TWH hot water isolation valve720can also be transitioned to a right hand TWH hot water isolation valve710by reversing the swappable process.

As shown inFIG.6AandFIG.6B, the swappable process (lower left) includes removing the drain assembly121from port196, removing the unused port plug165from port197, and removing the handle103by removing the screw105to remove the reversible handle stop109. The reversible handle stop109is then flipped over or rotated and/or and then reinstalled between handle103and the isolation valve body190. Finally, the drain assembly121is installed into port197, and the port plug165is installed into port196.

Typically, a TWH isolation valve can be configured at time of manufacture, at time of manufacture of the TWH were installed into a TWH product, and/or in the field when an installer installs the isolation valve, typically, but not necessarily, underneath a TWH.

A sensor or fluid connection to a diagnostic instrument (not shown inFIG.1,FIG.7) can be optionally installed into port196in the left hand configuration (right side ofFIG.1,FIG.7), or into port197in the right hand configuration (left side ofFIG.1,FIG.7).

In summary, and generally, with reference toFIG.1, A tankless water heater (TWH) isolation valve100includes a valve body190having a plug valve port191, a TWH port193, a water distribution system port198and a drain port (196,FIG.1or197). A plug valve101includes at least one plug seal104. The plug valve101is controlled by a rotatable plug valve handle103. The plug valve101is disposed through the plug valve port191and within the valve body190. The rotatable plug valve handle103includes a first plug valve handle position and a different rotated second plug valve handle position. In a normal operating mode in the first plug valve handle position (FIG.5AtoFIG.5D), the TWH port193is fluidly coupled to both of the drain port (196,FIG.1or197) and the water system distribution port198. In a drain mode (FIG.4AtoFIG.4D), the TWH port is fluidly coupled to the drain port (196,FIG.1or197), and the water system distribution port198is closed to the TWH port193as blocked by the plug seal104.

Also, generally, with reference toFIG.1, a tankless water heater (TWH) isolation valve100includes a valve body190having a plug valve port191, a TWH port193, a water distribution system port198, a first reversible port196, and a second reversible port197. The first reversible port196is disposed about opposite to the second reversible port197. A plug valve101includes at least one plug seal104. The plug valve101is controlled by a rotatable plug valve handle103. The plug valve101is disposed through the plug valve port191and within the valve body190. A drain valve121is mechanically coupled to either of the first reversible port196(FIG.6A, left side, right hand isolation valve configuration) or the second reversible port197(FIG.6B, right side, left hand isolation valve configuration), and a device (e.g. unused port plug165) is mechanically coupled a different one of the first reversible port196or the second reversible port197. The rotatable plug valve handle103has a first plug valve handle position and a different rotated second plug valve handle position. In a normal operating mode in the first plug valve handle position, the TWH port193is fluidly coupled to both of the drain valve121and the water system distribution port198. In a drain mode, the TWH port193is fluidly coupled to the drain valve121, and the water system distribution port198is closed to the TWH port as blocked by the plug seal104.

Yet another tankless water heater isolation valve assembly according to the Application is shown inFIG.7andFIG.13.

FIG.7is a drawing showing an exploded view of a tankless water heater isolation valve assembly1000. In this exemplary embodiment, the drain ports (isolation reversible port196, and isolation reversible port197) are now offset from the shut-off plug valve (e.g. raised above inFIG.7), and the pressure relief port195. In other words, the ports196,197are located on a separate plane from the port195. The drain ports are therefore unaffected by plug valve and are always in fluid contact with tankless water heater. One benefit of the arrangement ofFIG.7, is that the extra drain port can receive a sensor which is always in contact with the water. Any suitable sensor, including those described hereinabove can be used. Typically, the sensor will be a temperature sensor or a pressure sensor.

InFIG.7, both of the isolation reversible port196and isolation reversible port197are now raised above the isolation valve plug101and the plug valve assembly102. The isolation reversible port196, and isolation reversible port197are now part of an isolation reversible port assembly1010. Shown for reference inFIG.7are center lines1051,1061, and1071. The Isolation reversible port assembly1010can be seen to be aligned with center line1061, offset (e.g. above inFIG.7) and perpendicular to centerline1051of the plug valve assembly102.

FIG.8is a drawing showing exemplary right and left plates. InFIG.7, tab1011stops the rotation of stop plate1009, and in turn handle103. Stop plate1009includes a handle direction orientation mark1705, side designation text1701, and plate stop ledge1703.FIG.8is a drawing showing exemplary right and left plates Exemplary retainer ring1119(spring clip) snaps into trough1117to hold the plug valve assembly102together. Exemplary fastener1005affixes handle103to the isolation valve plug101.

Isolation reversible port assembly1010is still physically part of the tankless water heater isolation valve assembly1000, however the fluid flow through the isolation reversible port196and the isolation reversible port197is no longer controlled by the rotational position of the plug valve assembly102.

FIG.13is a drawing showing an exemplary pair of a hot water tankless water heater isolation valve assembly1000and a cold water tankless water heater isolation valve assembly1101. Note that the cold water tankless water heater isolation valve assembly1101does not need the pressure relief port195. The exemplary cold water tankless water heater isolation valve assembly1101can optionally excludes isolation reversible port197, or the isolation reversible port197can be present to allow for reversibility.

In summary, and with respect to exemplaryFIG.7, a tankless water heater (TWH) isolation valve100includes a valve body having a plug valve port191, a TWH port193, a water distribution system port198. A plug valve101includes at least one plug seal104. The plug valve101is controlled by a rotatable plug valve handle103. The plug valve101is disposed through the plug valve port191and within the isolation valve body190. A drain port assembly1010includes at least one drain port196, the at least one drain port196an integral part of the isolation valve body190. The drain port assembly1010is disposed between the TWH port193and the plug valve101. The drain port assembly1010(center line longitudinal axis1061) is offset from the plug valve101(center line longitudinal axis1051).

FIG.14is a block diagram showing how any of the embodiments of the TWH isolation valves described hereinabove can be used with a TWH in a building TWH system.

The method of changing from a right handed to a left handed configuration can includes the following steps:1) With purge valve facing the operator and handle placed in off position (handle stem pointing towards the operator), pull handle off from the valve, disconnecting from the rotor (rotating plug)2) Swap purge valve position with the brass plug on the opposite side of the valve3) Rotate the whole valve assembly so the purge valve is again facing the operator4) Remove Handle stop marked as “RIGHT HAND” and replace with additionally provided handle stop marked as “LEFT HAND”5) Reattach handle to the rotor (rotor still in off position), with the handle stem pointing towards the operator and in the same direction as the purge valve6) When complete, handle should now be on the left side, with operator facing purge valve, and handle stem pointing at the operator. Sealing portion of the rotor should be over the residential connection port for the hot side valve.7) Handle will now only rotate from pointing towards the operator to 90 degrees downward pointing towards direction of the flow (away from TWH on the hot side).

Hydraulic Isolation feature—When used in modular installations, such as where a plurality of hot water heaters share a common hot water main, a valve assembly according to the Application which further includes a hydraulic isolation feature can be field configured to provide hydraulic isolation of units that need service or repair while other units remain operating.FIG.12is a drawing showing an exemplary hot water heaters sharing a common hot water main.

FIG.9is a drawing showing an exploded view of a yet another tankless water heater isolation valve assembly with a hydraulic isolation feature.FIG.10is a drawing showing exemplary right and left plates with a notch for the hydraulic isolation feature ofFIG.9.

The tankless water heater isolation valve assembly ofFIG.9andFIG.10is similar to the tankless water heater isolation valve assembly ofFIG.7andFIG.8with the addition of hydraulic isolation position notches in the right and left stop plates.

To provide hydraulic isolation from a pressurized hot water main using the valve assembly ofFIG.9andFIG.10, the pressure-activated seal can be rotated 180 degrees from the bottom port to the upper port.

Generally, the plug valve is rotated into a hydraulic isolation position, and mechanically set to that position by the hydraulic isolation position notch901of the stop plate1009(FIG.9,FIG.10) seating over the tab1011(FIG.7,FIG.9).

As illustrated by the exemplary steps ofFIG.11AandFIG.11B.FIG.11Ais a drawing showing the first two exemplary steps to set hydraulic isolation.FIG.11Bis a drawing showing the last three exemplary steps to set hydraulic isolation. First, A) With the valve in the closed position (handle facing forwards), remove handle plug, handle and stop plate. B) Place handle back on rotor hub and rotate 180 degrees so handle is facing rearward. C) Remove handle and re-install stop plate aligning the notch (marked with a X) with the nub on the body. D) Re-install handle (facing to the rear) and handle plug. The valve will now provide hydraulic isolation from a pressurized hot water main and be locked closed to prevent operation of water heater. Finally, E) To place heater back in commission, reverse the above process.

It will be appreciated that variants of the above-disclosed and other features and functions, or alternatives thereof, may be combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.