Hot Water Re-Circulation Isolator System in Combination with Water Heater/Hydronic Heating System

Abstract

A heating system includes a water heater configured to heat water, a water recirculation loop configured to receive a first portion of hot water from the water heater and to provide the first portion of hot water back to the water heater, an air handler loop configured to receive a second portion of hot water from the water heater and to provide cooled water back to the water heater, and a controllable valve configured prevent the air handler from receiving the second portion of the hot water.

Claims

1. A heating system comprising: an air handler; a water heater configured to heat water; a water recirculation loop configured to receive a first portion of hot water from the water heater and to provide at least a portion of the first portion of hot water back to the water heater; an air handler loop configured to receive a second portion of hot water from the water heater and to provide cooled water back to the water heater; and a controllable valve configured prevent the air handler from receiving the second portion of hot water.

2. The heating system of claim 1, further comprising a thermostat configured to generate a thermostat signal based on a detected temperature.

3. The heating system of claim 2, wherein the thermostat is configured to provide the thermostat signal to the air handler, and wherein the controllable valve comprises a mechanical valve.

4. The heating system of claim 3, wherein the mechanical valve comprises a pressure valve.

5. The heating system of claim 4, wherein the air handler comprises an internal pump configured to pump the second portion of hot water from the water heater, wherein the thermostat signal causes the air handler to active the internal pump so as to pump the second portion of hot water from the water heater, and wherein the pumping of the second portion of hot water from the water heater creates pressure to open the pressure valve to cause the air handler to provide the cooled water back to the water heater.

6. The heating system of claim 3, wherein the thermostat is configured to provide the thermostat signal to the air handler via a wireless transmission.

7. The heating system of claim 2, wherein the thermostat is configured to provide the thermostat signal to the water heater, and wherein the controllable valve comprises an electronically actuated valve.

8. The heating system of claim 7, wherein the water heater is configured to transmit a valve control signal to cause the controllable valve to open to allow the air handler to receive the second portion of hot water from the air handler loop, and wherein the water heater is configured to transmit an air handler signal to cause the air handler to provide the cooled water back to the air handler loop.

9. The heating system of claim 7, wherein the thermostat is configured to provide the thermostat signal to the water heater via a wireless transmission.

10. The heating system of claim 1, wherein the water recirculation loop includes a dedicated return portion that is distinct from the air handler loop.

11. A method of heating water, the method comprising: heating, via a water heater, water; receiving, via a water recirculation loop, a first portion of hot water from the water heater; providing, via the water recirculation loop, at least a portion of the first portion of hot water back to the water heater; receiving, via an air handler loop, a second portion of hot water from the water heater; providing, via the air handler loop, cooled water back to the water heater; and preventing, via a controllable valve, an air handler from receiving the second portion of hot water.

12. The method of claim 11, further comprising generating, via a thermostat, a thermostat signal based on a detected temperature.

13. The method of claim 12, further comprising: providing, via the thermostat, the thermostat signal to the air handler, wherein the controllable valve comprises a pressure valve.

14. The method of claim 13, further comprising: pumping, via an internal pump of the air handler, the second portion of hot water from the water heater, wherein the thermostat signal causes the air handler to active the internal pump so as to pump the second portion of hot water from the water heater, and wherein the pumping of the second portion of hot water from the water heater creates pressure to open the pressure valve to cause the air handler to provide the cooled water back to the water heater.

15. The method of claim 13, wherein the providing, via the thermostat, the thermostat signal to the air handler comprises providing the thermostat signal to the air handler via a wireless transmission.

16. The method of claim 12, further comprising: providing, via the thermostat, the thermostat signal to the water heater, wherein the controllable valve comprises an electronically actuated valve.

17. The method of claim 16, further comprising: transmitting, via the water heater, a valve control signal to cause the controllable valve to open to allow the air handler to receive the second portion of hot water from the air handler loop; and transmitting, via the water heater, an air handler signal to cause the air handler to provide the cooled water back to the air handler loop.

18. The method of claim 16, wherein the providing, via the thermostat, the thermostat signal to the water heater comprises providing the thermostat signal to the water heater via a wireless transmission.

19. The method of claim 11, wherein the water recirculation loop includes a dedicated return portion that is distinct from the air handler loop.

20. A heating system for use with an input water source, the heating system comprising: a water heater configured to heat water; a water recirculation loop configured to receive a first portion of hot water from the water heater and to provide at least a portion of the first portion of hot water back to the water heater; an air handler loop configured to receive a second portion of hot water from the water heater and to provide cooled water back to the water heater; an input line valve configured to receive water from the input water source and to prevent cooled water from the air handler loop for flowing out to the input water source; and a controllable valve configured prevent an air handler from receiving the second portion of hot water.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The detailed description is set forth with reference to the accompanying drawings. In some instances, the use of the same reference numerals may indicate similar or identical items. Various embodiments may utilize elements and/or components other than those illustrated in the drawings, and some elements and/or components may not be present in various embodiments. Throughout this disclosure, depending on the context, singular and plural terminology may be used interchangeably.

[0018] FIG. 1 illustrates a prior art hot water recirculation isolator system in combination with a water heater/hydronic heating system having a dedicated recirculation loop return.

[0019] FIG. 2 illustrates a prior art hot water recirculation isolator system in combination with a water heater/hydronic heating system having a non-dedicated recirculation loop return.

[0020] FIG. 3 illustrates an example method for heating water in accordance with one or more embodiments of the present disclosure.

[0021] FIG. 4A illustrates a hot water recirculation isolator system in combination with a water heater/hydronic heating system having a dedicated recirculation loop return and having an electronically controlled valve in accordance with one or more embodiments of the present disclosure during hydronic heating and recirculation.

[0022] FIG. 4B illustrates the hot water recirculation isolator system in combination with a water heater/hydronic heating system of FIG. 4A without hydronic heating in accordance with one or more embodiments of the present disclosure.

[0023] FIG. 5A illustrates a hot water recirculation isolator system in combination with a water heater/hydronic heating system having a non-dedicated recirculation loop return and having an electronically controlled valve in accordance with one or more embodiments of the present disclosure during hydronic heating and recirculation.

[0024] FIG. 5B illustrates the hot water recirculation isolator system in combination with a water heater/hydronic heating system of FIG. 5A without hydronic heating in accordance with one or more embodiments of the present disclosure.

[0025] FIG. 6 schematically illustrates the water heater of FIGS. 4A-5B in accordance with one or more embodiments of the present disclosure.

[0026] FIG. 7A illustrates a hot water recirculation isolator system in combination with a water heater/hydronic heating system having a dedicated recirculation loop return and having a pressure controlled valve in accordance with one or more embodiments of the present disclosure during hydronic heating and recirculation.

[0027] FIG. 7B illustrates the hot water recirculation isolator system in combination with a water heater/hydronic heating system of FIG. 7A without hydronic heating in accordance with one or more embodiments of the present disclosure.

[0028] FIG. 8A illustrates a hot water recirculation isolator system in combination with a water heater/hydronic heating system having a non-dedicated recirculation loop return and having a pressure controlled valve in accordance with one or more embodiments of the present disclosure during hydronic heating and recirculation.

[0029] FIG. 8B illustrates the hot water recirculation isolator system in combination with a water heater/hydronic heating system of FIG. 8A without hydronic heating in accordance with one or more embodiments of the present disclosure.

DETAILED DESCRIPTION

[0030] The present disclosure is directed to hot water recirculation isolator systems in combination with a water heater/hydronic heating systems. The systems and methods disclosed herein are more energy efficient than the systems discussed above with reference to FIGS. 1-2. For example, the hot water recirculation isolator system in combination with a water heater and hydronic heating system disclosed herein may allow the recirculation water to flow only through the recirculation loop so as to prevent the recirculation water from flowing to the hydronic heating system when there is no need for heat. This is achieved by way of a controllable valve to close off the space heating loop when recirculation is on and the space heating loop is off. In some instances, the controllable valve is an electronically actuated valve that may be opened and closed electronically by a signal from the water heater. In other instances, the controllable valve is a mechanical valve. In some of these instances the mechanical valve is a pressure valve that is mechanically opened by water pressure.

[0031] The hot water recirculation isolator system in combination with a water heater and hydronic heating system disclosed herein may save energy over typical systems because when the controllable valve is closed, the water heater will only heat the water in the recirculation loop rather than heating water in both the recirculation loop and in the space heating loop.

[0032] Turning to the drawings, FIGS. 3-8B depict various systems and methods directed to example hot water recirculation isolator systems in combination with water heater/hydronic heating systems of the present disclosure.

[0033] FIG. 3 illustrates an example method 300 for heating water in accordance with one or more embodiments of the present disclosure. As depicted in FIG. 3, the method 300 starts (S302), and the air handler loop is active (S304). This will be described in greater detail with reference to FIGS. 4A, 5A, 7A, and 8A. For example, as depicted in FIG. 4A, the hot water recirculation isolator system in combination with a water heater/hydronic heating system 400 includes an air handler 402, a water heater 404, a thermostat 406, a water input line 408, an input line valve 410, an electronically actuated valve 412, a return valve 414, a water line 416, a water line 418, a recirculation line 420, a dedicated return line 422, a communication channel 424, a communication channel 426, and a communication channel 428.

[0034] The water heater 404 is configured to communicate with the thermostat 406 via the communication channel 424, to communicate with the air handler 402 via the communication channel 426, and to communicate with the electronically actuated valve 412 via the communication channel 428. When there is a need for space heating, the thermostat 406 sends a thermostat signal 430 to the water heater 404. This will be described in greater detail with reference to FIG. 6.

[0035] FIG. 6 schematically illustrates the water heater 404. The water heater 404 includes a controller 602, a memory 604, a communication component 606, and a user interface (UI) 608. The memory 604 has stored therein a heating program 610. The communication component 606 includes a radio 612 and an interface 614.

[0036] As depicted in FIG. 6, the radio 612 and the interface 614 are illustrated as individual devices. However, in some embodiments, the radio 612 and the interface 614 may be combined as a unitary device. Further, in this example, the controller 602, the memory 604, the communication component 606, and the UI 608 are illustrated as individual devices. However, in some embodiments, at least two of the controller 602, the memory 604, the communication component 606, and the UI 608 may be combined as a unitary device. Further, in some embodiments, at least one of the controller 602, the memory 604, the communication component 606, and the UI 608 may be implemented as a computer having tangible computer-readable media for carrying or having computer-executable instructions or data structures stored thereon, which may include any computer program product, apparatus or device that can be used to carry or store desired computer-readable program code in the form of instructions or data structures and that can be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor

[0037] Such a computer system/server may be described in the general context of computer system-executable instructions, such as program modules, being executed by a computer system. Generally, program modules may include routines, programs, objects, components, logic, data structures, and so on that perform particular tasks or implement particular abstract data types. Further, such a computer system/server may be practiced in distributed cloud computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed cloud computing environment, program modules may be located in both local and remote computer system storage media including memory storage devices.

[0038] Components of an example computer system/server may include, but are not limited to, one or more processors or processing units, a system memory, and a bus that couples various system components including the system memory to the processor.

[0039] The controller 602 may be implemented as a hardware processor such as a microprocessor, a multi-core processor, a single core processor, a field programmable gate array (FPGA), a microcontroller, an application specific integrated circuit (ASIC), a digital signal processor (DSP), or other similar processing device capable of executing any type of instructions, algorithms, or software for controlling the operation and functions of the water heater 404 in accordance with one or more embodiments of the present disclosure.

[0040] The memory 604 can store various programming and data. The heating program 610 includes instructions to enable the water heater 404 to operate in accordance with one or more embodiments of the present disclosure.

[0041] The radio 612 may include a Wi-Fi WLAN interface radio transceiver that is configured to communicate with the air handler 402, the thermostat 406, and the electronically actuated valve 412, as shown in FIGS. 4A-5B, and also may include a cellular transceiver configured to communicate with a cellular network. The radio 612 includes one or more antennas and communicates wirelessly. The water heater 404 can also be equipped with a radio transceiver/wireless communication circuit to implement a wireless connection in accordance with any protocols.

[0042] The interface 614 can include one or more connectors, such as RF connectors, or Ethernet connectors. The UI 608 may be any device or system to enable a user to interact with the controller 602.

[0043] In embodiments wherein any of the communication channel 424, the communication channel 426, and the communication channel 428 are wireless communication channels, the water heater 404 may communicate with the thermostat 406, the air handler 402, and the electronically actuated valve 412, respectively, via the radio 612. Alternatively, embodiments wherein any of the communication channel 424, the communication channel 426, and the communication channel 428 are wired communication channels, the water heater 404 may communicate with the thermostat 406, the air handler 402, and the electronically actuated valve 412, respectively, via the interface 614.

[0044] In operation, when the thermostat 406 sends the thermostat signal 430 to the water heater 404, the communication component 606 receives the thermostat signal 430. In embodiments where the communication channel 424 is a wireless communication channel, then radio 612 receives the thermostat signal 430. In embodiments where the communication channel 424 is a wired communication channel, then interface 614 receives the thermostat signal 430.

[0045] Returning to FIG. 4A, after the thermostat 406 sends the thermostat signal 430 to the water heater 404, the water heater 404 then sends a valve control signal 434 to electronically actuated valve 412. The electronically actuated valve 412 may be any type of valve that controls the flow of liquid and without the need for a pneumatic air supply. In some instances, the electronically actuated valve 412 may take the form of an electronically actuated solenoid or an electronically actuated ball valve. For example, as shown in FIG. 6, upon receiving the thermostat signal 430, the communication component 606 passes the thermostat signal 430 to the controller 602. The controller 602 then executes instructions stored in the heating program 610 to cause the communication component 606 to send the valve control signal 434 to the electronically actuated valve 412. In embodiments where the communication channel 428 is a wireless communication channel, then radio 612 sends the valve control signal 434. In embodiments where the communication channel 428 is a wired communication channel, then interface 614 sends the valve control signal 430.

[0046] Returning to FIG. 4A, the valve control signal 434 causes the electronically actuated valve 412 to open and allow water to flow to the air handler 402. The water heater 404 then sends an air handler signal 432 to the air handler 402. For example, as shown in FIG. 6, upon receiving the thermostat signal 430, the communication component 606 passes the thermostat signal 430 to the controller 602. The controller 602 then also executes instructions in the heating program 610 to cause the communication component 606 to send the air handler signal 432 to the air handler 402. In embodiments where the communication channel 426 is a wireless communication channel, then radio 612 sends the air handler signal 432. In embodiments where the communication channel 426 is a wired communication channel, then interface 614 sends the air handler signal 432.

[0047] Returning to FIG. 4A, the air handler signal 432 causes the air handler 404 to activate. The air handler 404 activates its internal pump to start flowing water. Water flows to the water heater 404 and causes the water heater 404 to activate and heat the water. Hot water flows out of the water heater 404 and into the air handler 402 via the water pipe 416. The air handler 402 exchanges heat from the water to air such that cooled water leaves the air handler 402 via an output 442 and flows back to an inlet 444 of the water heater 404 via the water pipe 418 so that the air handler loop 446 can repeat.

[0048] While the air handler loop 446 is active, a portion of the water from the outlet 436 of the water heater 404 flows into the recirculation line 420, through the return valve 414, through the dedicated return line 422, and back into the water heater 404 via an inlet 425, thus making a recirculation loop 448. The return valve 414 is a check valve or other suitable valve that prevents water from backflowing out of the recirculation loop 448 and into the air handler loop 446.

[0049] It should be noted that the recirculation loop 448 may include branches that feed to faucets throughout the structure. In particular, the purpose of the recirculation loop 448 is to maintain hot water throughout the hot water pipes within the building, such that there is less waiting time to have hot water when needed.

[0050] The above discussed operation of space heating with an air handler loop may additionally be performed in a system that does not have a dedicated return line. For example, FIG. 5A illustrates a hot water recirculation isolator system in combination with a water heater/hydronic heating system 500 having a non-dedicated recirculation loop return and having an electronically controlled valve in accordance with one or more embodiments of the present disclosure during hydronic heating and recirculation.

[0051] The hot water recirculation isolator system in combination with a water heater/hydronic heating system 500 is similar to the hot water recirculation isolator system in combination with a water heater/hydronic heating system 400 discussed above with reference to FIG. 4A. However, the hot water recirculation isolator system in combination with a water heater/hydronic heating system 500 does not include a dedicated return line. Instead, the hot water recirculation isolator system in combination with a water heater/hydronic heating system 500 includes a recirculation loop 506 having a recirculation line 502 and a return valve 504 that feeds into water line 418 in order to re-circulate water to the inlet 444 of the water heater 404. In this manner, while the air handler loop 446 is active, a portion of the water from the outlet 436 of the water heater 404 flows into the recirculation line 502, through the return valve 504, and back into the water heater 404 via the inlet 444, thus making a recirculation loop 506. The return valve 504 is a check valve or other suitable valve that prevents water from backflowing out of the recirculation loop 506 and into the air handler loop 446.

[0052] It should be noted that the recirculation loop 506 may include branches that feed to faucets throughout the structure. In particular, the purpose of the recirculation loop 506 is to maintain hot water throughout the hot water pipes within the building, such that there is less waiting time to have hot water when needed.

[0053] In the embodiments discussed above with reference to FIGS. 4A-6, an electronically controlled valve is a controllable valve configured prevent the air handler from receiving hot water. However, a mechanical valve may alternatively be used as a controllable valve configured prevent the air handler from receiving hot water. For example, FIG. 7A illustrates a hot water recirculation isolator system in combination with a water heater/hydronic heating system 700 having a dedicated recirculation loop return and having a pressure controlled valve in accordance with one or more embodiments of the present disclosure during hydronic heating and recirculation. As depicted in FIG. 7A, the hot water recirculation isolator system in combination with a water heater/hydronic heating system 700 includes the air handler 402, the water heater 404, a thermostat 702, the water input line 408, the input line valve 410, a pressure valve 704, the return valve 414, the water line 416, the water line 418, the recirculation line 420, the dedicated return line 422, and a communication channel 706. The air handler 402 is configured to communicate with the thermostat 702 via the communication channel 706.

[0054] The pressure valve 704 may be any mechanical, pressure activated valve, wherein the pressure of the water in the air handler 402 controls the operation of the pressure valve 704. For example, in some instances, the pressure valve 704 includes a direct-acting relief valve that includes a poppet exposed the pressure from the water in the air handler 402 opposed by a spring of a preset force. In other instances, the pressure valve 704 may be a pilot-operated relief valve that operates in two stages. A first stage, or pilot stage, includes a small, spring-biased relief valve that acts as a trigger to control a main relief valve in a second stage.

[0055] In certain embodiments, the pressure valve 704 is normally closed. That is, the repose position is the closed position. When there is a need for space heating, the thermostat 702 sends a thermostat signal to the air handler 402, which activates the air handler 402. The air handler 402 activates its internal pump to start flowing water. In doing so, the water pressure starts to build at the pressure valve 704, which forces the pressure valve 704 to open.

[0056] Water flows to the water heater 404 and causes the water heater 404 to activate and heat the water. Hot water flows out of the water heater 404 from output 436 and into the inlet 438 of the air handler 402 via the water line 416. The air handler 402 exchanges heat from the water to air, so cooled water leaves the air handler 402 at outlet 442 and flows back to the inlet 444 of the water heater 404 via water line 418 so that the air handler loop 446 can repeat.

[0057] While the air handler loop 446 is active, a portion of the water from the outlet 436 of the water heater 404 flows into the recirculation line 420, through the return valve 414, through the dedicated return line 422, and back into the water heater 404 via the inlet 425 thus making the recirculation loop 448. The return valve 414 is a check valve or other suitable valve that prevents water from backflowing out of the recirculation loop 448 and into the air handler loop 446.

[0058] It should be noted that the recirculation loop 448 may include branches that feed to faucets throughout the structure. In particular, the purpose of the recirculation loop 448 is to maintain hot water throughout the hot water pipes within the building, such that there is less waiting time to have hot water when needed.

[0059] The above discussed operation of space heating with an air handler loop may additionally be performed in a system that does not have a dedicated return line. For example, FIG. 8A illustrates a hot water recirculation isolator system in combination with a water heater/hydronic heating system 800 having a non-dedicated recirculation loop return and having an electronically controlled valve in accordance with one or more embodiments of the present disclosure during hydronic heating and recirculation. The hot water recirculation isolator system in combination with a water heater/hydronic heating system 800 is somewhat similar to the hot water recirculation isolator system in combination with a water heater/hydronic heating system 700 discussed above with reference to FIG. 7A. However, the hot water recirculation isolator system in combination with a water heater/hydronic heating system 800 does not include a dedicated return line. Instead, the hot water recirculation isolator system in combination with a water heater/hydronic heating system 800 includes a recirculation loop 806 having recirculation line 802 and a return valve 804 that feeds into water line 418 in order to re-circulate water to the inlet 444 of the water heater 404.

[0060] While the air handler loop 446 is active, a portion of the water from the outlet 436 of the water heater 404 flows into the recirculation line 802, through the return valve 804, and back into the water heater 404 via the inlet 444 thus making a recirculation loop 806. The return valve 804 is a check valve or other suitable valve that prevents water from backflowing out of the recirculation loop 806 and into the air handler loop 446.

[0061] It should be noted that the recirculation loop 806 may include branches that feed to faucets throughout the structure. In particular, the purpose of the recirculation loop 806 is to maintain hot water throughout the hot water pipes within the building, such that there is less waiting time to have hot water when needed.

[0062] Returning to FIG. 3, after the air handler loop is active (S304), the temperature is detected (S306). For example, as shown in FIGS. 4A and 5A, the thermostat 406 detects the ambient temperature in the building. Similarly, as shown in FIGS. 7A and 8A, the thermostat 702 detects the ambient temperature in the building.

[0063] After the temperature is detected (S306), it is determined whether the detected temperature is greater than or equal to a temperature threshold (S308). For example, as depicted in FIGS. 4A and 5A, the thermostat 406 may have a predetermined temperature threshold set therein. This temperature threshold may be set by a user by any method, an example of which includes using a graphic user interface on the thermostat 406 or associated application on a mobile device or the like. Further, the thermostat 406 may compare the detected ambient temperature with the temperature threshold to determine whether the detected temperature is greater than or equal to a temperature threshold.

[0064] Similarly, as shown in FIGS. 7A and 8A, the thermostat 702 may have a predetermined threshold temperature set therein and may determine whether the detected temperature is greater than or equal to a temperature threshold. If it is determined that the detected temperature is not greater than or equal to the temperature threshold (N at S308), then the air handler loop continues to be active (S310) and the temperature is again detected (return to S306). However, if it is determined that the detected temperature is greater than or equal to the temperature threshold (Y at S308), then the air handler loop is deactivated (S312).

[0065] FIG. 4B illustrates the hot water recirculation isolator system in combination with a water heater/hydronic heating system 400 without hydronic heating. As depicted in FIG. 4B, when there is no need for space heating, the electronically actuated valve 412 does not receive the valve control signal 434 from the water heater 404 to open. Accordingly, the electronically actuated valve 412 closes and prevents water from flowing to the air handler 402. When hot water recirculation is activated, the internal pump of the water heater 404 begins to flow water. The flow of water activates the water heater 404 and causes the water heater 404 to heat the water. Hot water flows out of the outlet 436 of the water heater 404 into the recirculation loop 448. Since the electronically actuated valve 412 is closed, water cannot flow into the air handler 402. In this manner, hot water flows through the recirculation loop 448 only and returns to the inlet 424 of the water heater 404 via the dedicated return line 422. The recirculation loop 448 then repeats.

[0066] The input line valve 414 is a check valve or other suitable valve that prevents water from flowing out to the main water source during operation of either the space heating function or the hot water recirculation function. The input line valve 414 may similarly function if placed in any of multiple locations, examples of which include at the inlet 438 of the air handler 402 and the outlet 442 of the air handler 402.

[0067] FIG. 5B illustrates the hot water recirculation isolator system in combination with a water heater/hydronic heating system 500 without hydronic heating. With reference to FIG. 5B, when there is no need for space heating, the electronically actuated valve 412 does not receive the valve control signal 434 from the water heater 404 to open. Accordingly, electronically actuated valve 412 closes and prevents water from flowing to the air handler 402. When hot water recirculation is activated, the internal pump of the water heater 404 begins to flow water. The flow of water activates the water heater 404 and causes the water heater 404 to heat the water. Hot water flows out of the outlet 436 of the water heater 404 into the recirculation loop 448. Since the electronically actuated valve 412 is closed, water cannot flow into the air handler 402. In this manner, hot water flows through the recirculation loop 448 only and returns to the inlet 444 of the water heater 404 via the water line 418. The recirculation loop 506 then repeats.

[0068] FIG. 7B illustrates the hot water recirculation isolator system in combination with a water heater/hydronic heating system 700 without hydronic heating. With reference to FIG. 7B, when there is no need for space heating, the pressure valve 704 remains closed because the internal pump of the air handler 402 is not producing water pressure to open the pressure valve 704. In a closed state, the pressure valve 704 prevents water from flowing to the air handler 402. When hot water recirculation is activated, the internal pump of the water heater 404 begins to flow water. The flow of water activates the water heater 404 and causes the water heater 404 to heat the water. Hot water flows out of the outlet 436 of the water heater 404 into and the recirculation loop 448. Since the pressure valve 704 is closed, water cannot flow into the air handler 402. In this manner, hot water flows through the recirculation loop 448 and returns to the inlet 425 of the water heater 404 via the dedicated return line 422. The recirculation loop 448 then repeats.

[0069] FIG. 8B illustrates the hot water recirculation isolator system in combination with a water heater/hydronic heating system 800 without hydronic heating. With reference to FIG. 8B, when there is no need for space heating, the pressure valve 704 remains closed because the internal pump of the air handler 402 is not producing water pressure to open the pressure valve 704. In a closed state, the pressure valve 704 prevents water from flowing to the air handler 402. When hot water recirculation is activated, the internal pump of the water heater 404 begins to flow water. The flow of water activates the water heater 404 and causes the water heater 404 to heat the water. Hot water flows out of the outlet 436 of the water heater 404 into and the recirculation loop 804. Since the pressure valve 704 is closed, water cannot flow into the air handler 402. In this manner, hot water flows through the recirculation loop 804 and returns to the inlet 444 of the water heater 404 via the water line 422. The recirculation loop 804 then repeats.

[0070] Returning to FIG. 3, after the air handler loop is deactivated (S312), method 300 stops (S314).

[0071] Typical hot water recirculation isolator systems in combination with a water heater/hydronic heating system are energy inefficient because they recirculate heated water through the air handler loop whether it is needed or not. However in accordance with one or more embodiments of the present disclosure, a controllable valve is used to prevent the air handler from receiving heated water when it is not required. As such, only water in the recirculation loop is heated when space heating is not needed. Therefore, the disclosed hot water recirculation isolator system in combination with a water heater/hydronic heating system is much more energy efficient as compared to prior art systems. In some embodiments, the controllable valve is a mechanical valve. In some of these embodiments, the mechanical valve is a pressure valve. In some other embodiments, the controllable valve is an electronically actuated valve.

[0072] It should be apparent that the foregoing relates only to certain embodiments of the present application and that numerous changes and modifications may be made herein by one of ordinary skill in the art without departing from the general spirit and scope of the disclosure.

[0073] Although specific embodiments of the disclosure have been described, numerous other modifications and alternative embodiments are within the scope of the disclosure. For example, any of the functionality described with respect to a particular device or component may be performed by another device or component. Further, while specific device characteristics have been described, embodiments of the disclosure may relate to numerous other device characteristics. Further, although embodiments have been described in language specific to structural features and/or methodological acts, it is to be understood that the disclosure is not necessarily limited to the specific features or acts described. Rather, the specific features and acts are disclosed as illustrative forms of implementing the embodiments. Conditional language, such as, among others, can, could, might, or may, unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments could include, while other embodiments may not include, certain features, elements, and/or steps. Thus, such conditional language is not generally intended to imply that features, elements, and/or steps are in any way required for one or more embodiments.