CN111684215A

CN111684215A - System and method for cleaning a chiller system

Info

Publication number: CN111684215A
Application number: CN201880088520.9A
Authority: CN
Inventors: 马克克雷·威廉·蒙泰思
Original assignee: Johnson Controls Technology Co
Current assignee: Johnson Controls Technology Co
Priority date: 2017-12-28
Filing date: 2018-12-27
Publication date: 2020-09-18
Also published as: US20190203992A1; KR20200100781A; EP3732407A1; JP2021508812A; WO2019133723A1

Abstract

In an embodiment of the present disclosure, a heating, ventilation, and air conditioning (HVAC) system includes: a refrigerant loop configured for flowing a refrigerant, and a purging system configured for purging the HVAC system of non-condensable gases (NCGs). The purge system includes a purge heat exchanger configured to receive a mixture of the NCG and the refrigerant. The purge heat exchanger is configured to separate the NCG in the mixture from the refrigerant in the mixture with a cooling fluid. The washing system also includes a thermoelectric assembly configured to remove heat from the cooling fluid.

Description

System and method for cleaning a chiller system

Cross Reference to Related Applications

The present application claims priority and benefit from U.S. provisional application serial No. 62/611,412 entitled "SYSTEMS AND METHODS for a chiller system A CHILLER SYSTEM [ system and method for cleaning a chiller system ] filed on 28.12.2017, which is incorporated herein by reference in its entirety for all purposes.

Background

The present application relates generally to a purge system for a chiller system.

Chiller systems or vapor compression systems utilize a working fluid, commonly referred to as a refrigerant, that changes phase between vapor, liquid, and combinations thereof in response to being subjected to different temperatures and pressures associated with operation of the vapor compression system. In a low pressure chiller system, some components of the low pressure chiller system operate at a lower pressure than the surrounding atmosphere. Due to the pressure differential, non-condensable gases (NCG), such as ambient air, may migrate into these low pressure components, which may result in inefficiencies in the low pressure cooler system. Thus, the low pressure chiller system can be purged of NCG for more efficient operation. However, conventional cleaning systems for removing NCG may utilize additional refrigerants with moderate or high Global Warming Potentials (GWPs).

Disclosure of Invention

In an embodiment of the present disclosure, a heating, ventilation, and air conditioning (HVAC) system includes: a refrigerant loop configured for flowing a refrigerant, and a purging system configured for purging the HVAC system of non-condensable gases (NCGs). The purge system includes a purge heat exchanger configured to receive a mixture of the NCG and the refrigerant. The purge heat exchanger is configured to separate NCG in the mixture from refrigerant in the mixture with a non-refrigerant fluid. The cleaning system also includes a thermoelectric assembly configured to remove heat from the non-refrigerant fluid.

In another embodiment of the present disclosure, a heating, ventilation and air conditioning (HVAC) system includes: a refrigerant loop; a compressor disposed along the refrigerant loop and configured to circulate a refrigerant through the refrigerant loop; an evaporator disposed along the refrigerant loop and configured for placing the refrigerant in heat exchange relationship with a first cooling fluid; a condenser disposed along the refrigerant loop and configured for placing the refrigerant in heat exchange relationship with a second cooling fluid; and a purging system configured to purge the HVAC system of non-condensable gases (NCGs). The purge system includes a purge heat exchanger configured to separate a mixture drawn from the condenser with a first refrigerant stream of the refrigerant drawn from the evaporator and with a non-refrigerant fluid. The mixture includes the NCG and a second of the refrigerant streams drawn from the condenser. The purge heat exchanger is configured to separate the NCG in the mixture from a second refrigerant stream in the mixture. The washing system also includes a thermoelectric assembly configured to remove thermal energy from the first refrigerant flow and the non-refrigerant fluid.

In another embodiment of the present disclosure, a heating, ventilation and air conditioning (HVAC) system includes: a refrigerant loop; a compressor disposed along the refrigerant loop and configured to circulate a refrigerant through the refrigerant loop; an evaporator disposed along the refrigerant loop and configured for placing the refrigerant in heat exchange relationship with a first cooling fluid; a condenser disposed along the refrigerant loop and configured for placing the refrigerant in heat exchange relationship with a second cooling fluid; and a purging system configured to purge the HVAC system of non-condensable gases (NCGs). The purge system includes a purge heat exchanger configured to receive a mixture of the NCG and the refrigerant. The purge heat exchanger is configured to separate NCG in the mixture from refrigerant in the mixture with a cooling fluid in a cooling fluid loop. The washing system further comprises a thermoelectric assembly configured to cool the cooling fluid together with an intermediate fluid in an open fluid loop.

Drawings

FIG. 1 is a perspective view of an embodiment of a building that may utilize a heating, ventilation, and air conditioning (HVAC) system in a commercial environment, according to an aspect of the present disclosure;

FIG. 2 is a perspective view of an embodiment of an HVAC system according to one aspect of the present disclosure;

FIG. 3 is a schematic illustration of an embodiment of the HVAC system of FIG. 2, in accordance with an aspect of the present disclosure;

FIG. 4 is a schematic illustration of an embodiment of the HVAC system of FIG. 2, in accordance with an aspect of the present disclosure;

FIG. 5 is a schematic view of a thermoelectric assembly of the HVAC system of FIG. 2, according to an aspect of the present disclosure;

FIG. 6 is a schematic view of a thermoelectric assembly of the HVAC system of FIG. 2 according to an aspect of the present disclosure.

FIG. 7 is a schematic illustration of an embodiment of the HVAC system of FIG. 2, in accordance with an aspect of the present disclosure;

FIG. 8 is a schematic view of an embodiment of the HVAC system of FIG. 2 in accordance with an aspect of the present disclosure;

FIG. 9 is a schematic illustration of an embodiment of the HVAC system of FIG. 2, in accordance with an aspect of the present disclosure;

FIG. 10 is a schematic illustration of an embodiment of the HVAC system of FIG. 2, in accordance with an aspect of the present disclosure;

FIG. 11 is a schematic illustration of an embodiment of the HVAC system of FIG. 2, in accordance with an aspect of the present disclosure;

FIG. 12 is a schematic view of an embodiment of the HVAC system of FIG. 2 in accordance with an aspect of the present disclosure;

FIG. 13 is a schematic diagram of an embodiment of the HVAC system of FIG. 2 in accordance with an aspect of the present disclosure;

FIG. 14 is a schematic illustration of an embodiment of a heat exchanger of the HVAC system of FIG. 2, according to an aspect of the present disclosure; and

FIG. 15 is a schematic view of an embodiment of a heat exchanger of the HVAC system of FIG. 2 according to an aspect of the present disclosure.

Detailed Description

Embodiments of the present disclosure include a purging system that may improve purging efficiency in a heating, ventilation, and air conditioning (HVAC) system. For example, in certain low pressure HVAC systems, the evaporator may draw in non-condensable gases (NCGs), such as ambient air from the atmosphere, due to the pressure differential between the evaporator and the atmosphere. The NCG may travel through the HVAC system and eventually collect within the condenser. These NCGs can be detrimental to the overall performance of the HVAC system and should therefore be removed. Thus, the presently disclosed embodiments may efficiently purge the HVAC system of NCGs via the purge system. For example, the purge system may draw a mixture of NCG and refrigerant from the condenser. The purge system may then utilize a purge heat exchanger (e.g., a purge coil in a purge chamber) to lower the temperature of the mixture or remove heat from the mixture to condense the refrigerant, thereby separating the refrigerant from the NCG due to the increased density of the refrigerant as a byproduct of the refrigerant condensation. In particular, the purge system may flow a cooling fluid through a purge coil of the heat exchanger to condense the refrigerant and separate the mixture. In certain embodiments, the cooling fluid may be cooled via one or more thermoelectric assemblies. Further, in certain embodiments, the cooling fluid may also be cooled via a secondary cooling fluid that is also cooled via the thermoelectric assembly. In some embodiments, the purge heat exchanger may include two separate purge coils that may utilize separate cooling fluids to cool the mixture.

Turning now to the drawings, FIG. 1 is a perspective view of an embodiment of an environment for a heating, ventilation, and air conditioning (HVAC) system 10 in a building 12 for a typical commercial environment. HVAC system 10 may include a vapor compression system 14 that supplies a cooling liquid that may be used to cool building 12. The HVAC system 10 may also include a boiler 16 to supply warm liquid to heat the building 12 and to circulate air through the air distribution system of the building 12. The air distribution system may also include an air return duct 18, an air supply duct 20, and/or an air handler 22. In some embodiments, the air handler 22 may include a heat exchanger connected to the boiler 16 and the vapor compression system 14 by a conduit 24. The heat exchanger in air handler 22 may receive heated liquid from boiler 16 or cooled liquid from vapor compression system 14, depending on the mode of operation of HVAC system 10. The HVAC system 10 is shown with a separate air handler on each floor of the building 12, but in other embodiments the HVAC system 10 may include an air handler 22 and/or other components that may be shared between two or more floors.

Fig. 2 and 3 are embodiments of a vapor compression system 14 that may be used in the HVAC system 10. The vapor compression system 14 may circulate refrigerant through a circuit beginning with a compressor 32. The circuit may also include a condenser 34, expansion valve(s) or expansion device(s) 36, and a liquid cooler or evaporator 38. Vapor compression system 14 can further include a control panel 40 (e.g., a controller) having an analog-to-digital (a/D) converter 42, a microprocessor 44, a non-volatile memory 46, and/or an interface board 48.

Some examples of fluids that may be used as refrigerants in vapor compression system 14 are Hydrofluorocarbon (HFC) -based refrigerants (e.g., R-410A, R-407, R-134a, Hydrofluoroolefins (HFO)), "natural" refrigerants (like ammonia (NH)₃) R-717, carbon dioxide (C)O₂) R-744), or a hydrocarbon-based refrigerant, water vapor, a refrigerant having a low Global Warming Potential (GWP), or any other suitable refrigerant. In some embodiments, the vapor compression system 14 may be configured to efficiently utilize refrigerant having a normal boiling point of about 19 degrees celsius (66 degrees fahrenheit or less) at one atmosphere (relative to medium pressure refrigerant such as R-134a, also referred to as low pressure refrigerant). As used herein, "normal boiling point" may refer to the boiling point temperature measured at one atmosphere of pressure.

In some embodiments, vapor compression system 14 may use one or more of a Variable Speed Drive (VSD)52, a motor 50, a compressor 32, a condenser 34, an expansion valve or device 36, and/or an evaporator 38. Motor 50 may drive compressor 32 and may be powered by a Variable Speed Drive (VSD) 52. VSD 52 receives Alternating Current (AC) power having a particular fixed line voltage and fixed line frequency from an AC power source and provides power having a variable voltage and frequency to motor 50. In other embodiments, the motor 50 may be powered directly by an AC or Direct Current (DC) power source. The motor 50 may comprise any type of electric motor that may be powered by a VSD or directly from an AC or DC power source, such as a switched reluctance motor, an induction motor, an electronically commutated permanent magnet motor, or another suitable motor.

The compressor 32 compresses a refrigerant vapor and delivers the vapor to the condenser 34 through a discharge passage. In some embodiments, the compressor 32 may be a centrifugal compressor. The refrigerant vapor pumped by the compressor 32 to the condenser 34 may transfer heat to a cooling fluid (e.g., water or air) in the condenser 34. The refrigerant vapor may condense to a refrigerant liquid in the condenser 34 as a result of heat transfer with the cooling fluid. The refrigerant liquid from the condenser 34 may flow through an expansion device 36 (which is intended to reduce the temperature and pressure of the refrigerant liquid) to an evaporator 38. In the embodiment illustrated in fig. 3, the condenser 34 is water cooled and includes a tube bundle 54 connected to a cooling tower 56 that supplies a cooling fluid to the condenser.

The refrigerant liquid delivered to the evaporator 38 may absorb heat from another cooling fluid, which may or may not be the same cooling fluid used in the condenser 34. The refrigerant liquid in the evaporator 38 may undergo a phase change from refrigerant liquid to refrigerant vapor. As shown in the illustrated embodiment of fig. 3, the evaporator 38 may include a tube bundle 58 having a supply line 60S and a return line 60R connected to a cooling load 62. A cooling fluid (e.g., water, ethylene glycol, calcium chloride brine, sodium chloride brine, or any other suitable fluid) of the evaporator 38 enters the evaporator 38 via a return line 60R and exits the evaporator 38 via a supply line 60S. Evaporator 38 may reduce the temperature of the cooling fluid in tube bundle 58 via heat transfer with a refrigerant. The tube bundle 58 in the evaporator 38 can include a plurality of tubes and/or a plurality of tube bundles. In any event, the refrigerant vapor exits the evaporator 38 and returns to the compressor 32 through a suction line to complete the cycle.

Fig. 4 is a schematic diagram of the vapor compression system 14 with an intermediate circuit 64 coupled between the condenser 34 and the expansion device 36. The intermediate circuit 64 may have an inlet line 68 fluidly connected directly to the condenser 34. In other embodiments, the inlet line 68 may be indirectly fluidly coupled to the condenser 34. As shown in the illustrated embodiment of fig. 4, inlet line 68 includes a first expansion device 66 positioned upstream of an intermediate vessel 70. In some embodiments, the intermediate vessel 70 may be a flash tank (e.g., a flash intercooler). In other embodiments, intermediate vessel 70 may be configured as a heat exchanger or "surface economizer". In the illustrated embodiment of fig. 4, the intermediate vessel 70 functions as a flash tank, and the first expansion device 66 is configured to reduce the pressure of (e.g., expand) the refrigerant liquid received from the condenser 34. During the expansion process, a portion of the liquid may vaporize, and thus the intermediate vessel 70 may be used to separate the vapor from the liquid received from the first expansion device 66. Additionally, the intermediate container 70 may provide for further expansion of the refrigerant liquid as the refrigerant liquid experiences a pressure drop upon entering the intermediate container 70 (e.g., due to a rapid increase in volume upon entering the intermediate container 70). The vapor in the intermediate vessel 70 may be drawn by the compressor 32 through a suction line 74 of the compressor 32 or through a centrifugal compressor. In other embodiments, the vapor in the intermediate vessel may be drawn to an intermediate stage (e.g., not a suction stage) of the compressor 32. The liquid collected in the intermediate container 70 may be at a lower enthalpy than the refrigerant liquid exiting the condenser 34 due to expansion in the expansion device 66 and/or the intermediate container 70. Liquid from intermediate vessel 70 can then flow in line 72 through second expansion device 36 to evaporator 38.

In some embodiments, the evaporator 38 may function at a pressure lower than ambient pressure when the vapor compression system 14 is in operation. Thus, the NCG may be drawn into the evaporator 38 and move through the compressor 32 to accumulate in the condenser 34. These NCGs may result in inefficient operation of the vapor compression system 14 because the NCG may act as an insulator that prevents efficient heat transfer from the refrigerant to the cooling fluid (e.g., water or air) within the condenser 34. Accordingly, the vapor compression system 14 may include features for purging the vapor compression system 14 of NCGs.

In particular, the vapor compression system 14 may include a purge system 80 for purging the vapor compression system 14 of NCGs. As mentioned above, the purge system 80 may purge the vapor compression system 14 at least in part by reducing the temperature of or removing heat from the mixture of NCG and refrigerant vapor withdrawn from the condenser 34, thereby condensing the refrigerant vapor and separating the refrigerant from the NCG. Specifically, the cleaning system 80 may remove heat from the mixture via a cooling fluid that may be cooled by utilizing one or more thermoelectric assemblies 82, as shown in fig. 5 and 6. Each thermoelectric assembly 82 may include a set of conductive plates (such as a hot side 84 and a cold side 86) and a thermoelectric device 88 (such as a set of semiconductors). The conductive plate may be coupled to the thermoelectric device 88 via thermal glue. Thermoelectric device 88 may include a set of extrinsic doped semiconductors having an electrical imbalance, such as a positive (P-type) semiconductor or a negative (N-type) semiconductor that may carry positive or negative charges, respectively. For example, heat may be absorbed by cold side 86, transferred through thermoelectric device 88, and released through hot side 84. In practice, the thermoelectric assembly 82 may create a temperature difference or thermal gradient between the cold side 86 and the hot side 84 based on the electrical energy difference. Further, a higher temperature difference may decrease the heat removal capability of the thermoelectric assembly 82, while a smaller temperature difference may increase the heat removal capability of the thermoelectric assembly 82. Each thermoelectric assembly 82 may induce an electrical gradient within the thermoelectric assembly 82 using the power supply 90. The power source 90 may be any suitable power source, such as an electrical grid, a battery, a solar panel, a generator, a gas engine, the vapor compression system 14, or any combination thereof. The thermoelectric assembly 82 may convert the electrical gradient into a thermal gradient through a thermoelectric effect or a Peltier-Seebeck (Peltier-Seebeck) effect.

The thermoelectric assembly 82 may utilize a thermal gradient to absorb heat from the fluid 92 flowing within and/or disposed within the conduit 94. The cold side 86 of the thermoelectric assembly 82 may be coupled to the conduit 94 via a heat sink 96 and/or thermal paste 98, which may conduct or transfer heat from the fluid 92 to the thermoelectric device 88, thereby cooling the fluid 92 within the conduit 94. Further, the hot side 84 of the thermoelectric assembly 82 may be coupled to another heat sink 96, which may be configured to remove heat from the hot side 84. To this end, the thermoelectric assembly 82 may also include a fan 100 configured to draw in ambient air 102 through the side of the heat sink 96 and to exhaust the heated ambient air 102 to the ambient environment. In this manner, the ambient air 102 may remove heat from the heat sink 96 as the fan 100 draws ambient air 102 through the heat sink 96 and forces the ambient air 102 out of the thermoelectric assembly 82 as heated air as the temperature increases.

As discussed herein, in some embodiments, additionally or in the alternative, the hot side 84 of the thermoelectric assembly 82 may be coupled to another conduit 94 having another fluid 92, which may also be cooled by an amount and configured to remove heat from the hot side 84. In this way, the temperature of the cold side 86 may be reduced due to the fact that the hot side 84 may be cooled to a temperature that is lower than the temperature of the ambient air 102. Indeed, the heat removal capability of the thermoelectric assembly 82 may be improved due at least in part to the reduced temperatures and temperature differences of the cold side 86 and the hot side 84. Still further, in some embodiments, the thermoelectric assembly 82 may include more than one set of cold side 86, thermoelectric device 88, and hot side 84. For example, the conduit 94 may be coupled to the first cold side 86, which is coupled to the first hot side 84 via the first thermoelectric device 88. Additionally, the first hot side 84 may be coupled to a second cold side 86, which in turn is coupled to the second hot side 84 via a second thermoelectric device 88. The second hot side 84 may then be coupled to any suitable heat removal system, such as a heat sink 96, fan 100, and/or duct 94 as discussed above. In fact, any suitable number of sets of cold side 86, thermoelectric devices 88, and hot side 84 may be stacked within thermoelectric assembly 82.

As illustrated in fig. 7-13, the vapor compression system 14 may include a purge system 80 configured to remove NCGs, such as ambient air, from the vapor compression system 14. To this end, the purge system 80 may include one or more thermoelectric assemblies 82, one or more pumps 110 (such as vacuum pumps, liquid pumps, and/or compressors), one or more shut-off valves 112, and a purge heat exchanger 114. The cleaning heat exchanger 114 may further include one or more cleaning coils 116 within the cleaning chamber 118. Further, it should be noted that the catheter discussed in fig. 7-13 may be similar to the catheter 94 of fig. 5 and 6.

Further, the vapor compression system 14 may utilize the controller 120 to control certain operational aspects of the purge system 80. The controller 120 may be any device employing a processor 122 (which may represent one or more processors), such as an application specific processor. The controller 120 may also include a memory device 124 for storing instructions executable by the processor 122 for performing the methods and control actions described herein for the washing system 80. Processor 122 may include one or more processing devices, and memory device 124 may include one or more tangible, non-transitory machine-readable media. By way of example, such machine-readable media can comprise RAM, ROM, EPROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, etc., or any other medium which can be used to carry or store desired program code in the form of machine-executable instructions or data structures and which can be accessed by the processor 122 or by any general purpose or special purpose computer or other machine with a processor.

To this end, the controller 120 may be communicatively coupled to one or more components of the washing system 80 via a communication system 126. In some embodiments, the communication system 126 may communicate over a wireless network (e.g., wireless local area network [ WLAN ], wireless wide area network [ WWAN ], near field communication [ NFC ]). In some embodiments, the communication system 126 may communicate over a wired network (e.g., local area network [ LAN ], wide area network [ WAN ]). For example, as shown in fig. 7-13, the controller 120 may be in communication with various elements of the washing system 80 (such as the pump 110, the thermoelectric assembly 82, the shut-off valve 112, and other components). In some embodiments, the functions of the controller 120 and the control panel 40 (fig. 3 and 4) as described herein may be controlled by a single controller. In some embodiments, the single controller may be the control panel 40 or the controller 120.

As discussed in further detail below, the cooling fluid may exchange heat with a mixture of refrigerant vapor and NCG drawn from the condenser 34 or from another portion of the system as the cooling fluid flows through the purge coil 116 of the purge heat exchanger 114. As mentioned above, since the vapor compression system 14 is at a low pressure relative to ambient pressure when operating, the NCG may be drawn into the evaporator 38 and travel through the vapor compression system 14 to accumulate in the condenser 34. Specifically, NCG may accumulate in one or more portions of the condenser 34. Thus, a mixture of NCG and refrigerant vapor may be withdrawn from one or more portions of the condenser 34. Generally, during normal operation, one or more portions of the NCG accumulation may be substantially below the discharge baffle, near the middle of the condenser 34, near the outlet of the condenser 34, near the top of the condenser 34, or any combination thereof.

The NCG that has accumulated in the condenser 34 may be mixed with the refrigerant vapor. The mixture of NCG and refrigerant vapor may be drawn into the purge chamber 118 of the purge heat exchanger 114 through conduit 128, which may be due at least in part to the temperature and/or pressure differential created by the cooling fluid passing through the purge coil 116 of the purge heat exchanger 114. In some embodiments, a compressor 129 may be disposed along conduit 128. The compressor 129 may pump the mixture of NCG and refrigerant vapor from the condenser 34 into the purge chamber 118 of the purge heat exchanger 114. In particular, the compressor 129 is configured to increase the pressure of the mixture before the mixture enters the purge heat exchanger 114. In this manner, the temperature at which the refrigerant vapor in the mixture condenses within the purge heat exchanger 114 increases, thereby reducing the load on the purge system 80.

As the mixture of NCG and refrigerant vapor comes into contact with the low temperature surfaces of the purge coil 116, the refrigerant vapor will condense into a refrigerant liquid and create a partial vacuum within the purge chamber 118 of the purge heat exchanger 114, drawing more of the mixture of NCG and refrigerant vapor from the condenser 34 through conduit 128. In some embodiments, as mentioned above, due to the compressor 129, the mixture of NCG and refrigerant vapor may be drawn through the conduit 128 and into the purge heat exchanger 114. Further, as the mixture of NCG and refrigerant vapor enters the purge heat exchanger 114 and the refrigerant vapor condenses into refrigerant liquid, the refrigerant liquid will collect at the bottom of the purge heat exchanger 114. Indeed, due at least in part to the density difference between the condensed refrigerant liquid and the NCG, NCG and other uncondensed refrigerant vapor will collect toward the top of the purge heat exchanger 114, while the condensed refrigerant liquid will collect at the bottom of the purge heat exchanger 114. Thus, as more refrigerant vapor in the mixture of NCG and refrigerant vapor condenses within the purge heat exchanger 114, the level of refrigerant liquid within the purge heat exchanger 114 will rise.

Once the level of refrigerant liquid has reached a predetermined threshold in the purge heat exchanger 114, the refrigerant liquid will be discharged through conduit 130 to the condenser 34, the evaporator 38, or both, and the NCG will be pumped out of the purge heat exchanger 114 by vacuum pump 132 through conduit 134. The vacuum pump 132 may then exhaust the NCG to the atmosphere. In some embodiments, the NCG may be at a high pressure within the purge heat exchanger 114 relative to atmospheric pressure because the compressor 129 increases the pressure of the mixture of the NCG and the refrigerant vapor before the mixture enters the purge heat exchanger 114. Therefore, because of the pressure difference between the NCG inside the purge heat exchanger 114 and the atmosphere, the NCG can be discharged to the atmosphere through the shutoff valve 112 of the conduit 134 without using the vacuum pump 132.

In some embodiments, the purge heat exchanger 114 may be disposed vertically above the condenser 34 and the evaporator 38. In this manner, refrigerant liquid may flow to the condenser 34, the evaporator 38, or both, due at least in part to a head pressure differential created by the height differential of the purge heat exchanger 114 relative to the condenser 34 and the evaporator 38. In some embodiments, the condenser 34 may be disposed vertically above the evaporator 38, thereby allowing refrigerant liquid to flow more easily from the purge heat exchanger 114 to the evaporator 38 than to the condenser 34.

In some embodiments, the cleaning heat exchanger 114 may include one or more sensors 138, which may include one or more temperature sensors, pressure sensors, level sensors, ultrasonic sensors, or any combination thereof. For example, one sensor 138 of the one or more sensors 138 may measure a level of refrigerant liquid within the purge heat exchanger 114 and send data regarding the level to the controller 120. If the liquid level approaches, matches, and/or exceeds a predetermined liquid level threshold, the controller 120 may send a signal to one or more of the shutoff valves 112 to allow refrigerant liquid to drain to the condenser 34, the evaporator 38, or both, as described above. Similarly, the controller 120 may send a signal to the pump 132 and/or one or more of the shutoff valves 112 to release the NCG to the atmosphere through the pump 132.

In some embodiments, the controller 120 may determine whether a large or predetermined amount of NCG is present within the condenser 34 before allowing the mixture of NCG and refrigerant vapor to enter the purge heat exchanger 114, such as by activating one or more of the shutoff valves 112. To determine whether a large or predetermined amount of NCG is present within the condenser 34, another sensor 138 of the one or more sensors 138 may measure one or more parameters related to the performance of the vapor compression system 14 and send data indicative of the one or more parameters to the controller 120 for analysis and processing. Specifically, the controller 120 may determine the performance level of the vapor compression system 14 based on one or more parameters. If the controller 120 determines that the performance level of the vapor compression system 14 is below the predetermined threshold, the controller 120 may allow the condenser 34 to be purged by opening the appropriate shutoff valve 112 and allowing a mixture of NCG and refrigerant vapor to flow from the condenser 34 to the purge heat exchanger 114, as described above. In some embodiments, the controller 120 may purge the condenser 34 based on a predetermined schedule, as described above.

Additionally or in the alternative, one of the sensors 138 may measure the saturation temperature and the actual temperature within the condenser 34 and send data indicative of the saturation temperature and the actual temperature to the controller 120 for analysis and processing. The controller 120 may then determine whether the saturation temperature substantially matches the actual temperature. If the saturation temperature does not substantially match the actual temperature, the controller 120 may allow the condenser 34 to be purged by opening the appropriate shutoff valve 112 and allowing the mixture of NCG and refrigerant vapor to flow from the condenser 34 to the purge heat exchanger 114, as described above.

As discussed herein, the purge heat exchanger 114 may receive a cooling fluid flowing through a purge coil 116 to condense the refrigerant vapor drawn from the condenser 34. In some embodiments, the cleaning coil 116 may include internal fins and/or external fins configured to increase the rate of heat transfer between the cleaning coil 116, the fluid within the cleaning coil 116, and/or the fluid external to the cleaning coil 116 and internal to the cleaning heat exchanger 114. Fig. 7-13 depict an embodiment of a cleaning system 80 for cooling fluid flowing through the cleaning coil 116. For example, as shown in fig. 7, the purge system 80 may include a closed fluid loop 160 configured to cool a fluid and flow the cooled fluid through the purge coil 116 to condense refrigerant vapor within the purge heat exchanger 114. In particular, the fluid within the closed fluid loop 160 may be a brine, and/or a water/glycol mixture, having a low freezing point.

The closed fluid loop 160 may utilize a liquid pump 162 to pump fluid through a conduit 164 of the closed fluid loop 160 and the wash coil 116. In practice, the liquid pump 162 may be a modified pump configured to pump saline, and/or a water/glycol mixture. Further, as shown, a plurality of thermoelectric assemblies 82 may be coupled to the conduit 164 and configured to remove heat from the fluid as it flows through the conduit 164, as described above with reference to fig. 5 and 6. There may be any suitable number of thermoelectric assemblies 82 coupled to the conduit 164.

In certain embodiments, as shown in FIG. 8, the cleaning system 80 may utilize a fluid from another source, such as a cooling fluid of the cooling load 62 (FIGS. 3 and 4). In other words, the cleaning system 80 may utilize fluid from a cooling system of a building, such as the building 12 (FIG. 1), through the open fluid loop 165. In certain embodiments, the fluid may be water, brine, or a water/glycol mixture. In particular, the liquid pump 162 of the open fluid loop 165 may draw fluid from the supply line 60S through the conduit 166 and supply the fluid to the wash coil 116 of the wash heat exchanger 114. As discussed above, as the fluid flows through the conduit 166 to the wash coil 116, the fluid may be cooled via the thermoelectric assembly 82, which is coupled to the conduit 166 and configured to remove heat from the fluid. In this manner, the cleaning coil 116 may receive fluid that has been cooled via the thermoelectric module 82. As the cooling fluid flows through the purge coil 116, the refrigerant vapor from the condenser 34 may condense within the purge chamber 118. After flowing through the cleaning coil 116, the fluid may flow back into the supply line 60S. In practice, the amount of fluid drawn from the supply line 60S is negligible relative to the total mass flow of fluid through the supply line 60S. Further, the fluid drawn from the supply line 60S and directed to the cleaning coil 116 may be at a temperature lower than ambient temperature due, at least in part, to the heat exchange process within the upper located evaporator 38. Accordingly, the thermoelectric module 82 may remove a reduced amount of heat from the fluid of the open fluid loop 165 to cause the fluid at a sufficiently low temperature to condense and purge the refrigerant vapor within the heat exchanger 114.

In certain embodiments, as shown in fig. 9, the cleaning system 80 may utilize cooling fluid from the closed fluid loop 160 and cooling fluid from the open fluid loop 165, which may serve similar functions to the embodiments discussed with reference to fig. 7 and 8, respectively. In particular, the closed fluid loop 160 may utilize a liquid pump 162 to flow fluid through a conduit 168 and through the cleaning coil 116. As the fluid flows through the conduit 168, the thermoelectric assembly 82 coupled to the conduit 168 may remove heat from the fluid, thereby cooling the fluid. In practice, the fluid may be brine, water, and/or a water/glycol mixture. Thus, liquid pump 162 of closed fluid loop 160 may be a modified pump configured to pump water, brine, and/or a water/glycol mixture.

As shown in the embodiment of fig. 9, the washing system 80 may also include an open fluid loop 165 that may utilize fluid from a cooling system of a building, such as the building 12 (fig. 1). In particular, the liquid pump 162 of the open fluid loop 165 may draw fluid from the supply line 60S and pump the fluid through the conduit 170 to the wash coil 116 of the wash heat exchanger 114. As the fluid flows through the conduit 170 to the wash coil 116, the thermoelectric assembly 82 coupled to the conduit 170 may remove heat from the fluid, thereby further cooling the fluid. In certain embodiments, the fluid drawn from the supply line 60S may be water, brine, or a water/glycol mixture. Thus, in such embodiments, the liquid pump 162 of the open fluid loop 165 may be configured to pump water, brine, or a water/glycol mixture, respectively.

As discussed above, the closed fluid loop 160 and the open fluid loop 165 may flow cooling fluid through the wash coil 116 of the wash heat exchanger 114. Specifically, in certain embodiments, the purge heat exchanger 114 may include two separate purge coils 116 that may separately receive cooling fluid from separate fluid loops (such as from the closed fluid loop 160 and from the open fluid loop 165), as discussed in further detail below in fig. 14. Further, as discussed in further detail below, the purge heat exchanger 114 may include a single purge coil 116 configured to receive cooling fluid from separate fluid loops (such as from both the closed fluid loop 160 and the open fluid loop 165) at separate times based on operation of the one or more shut-off valves 112, as discussed in further detail below in fig. 15. Additionally or in the alternative, the cleaning coil 116 may receive a mixture of fluids from separate fluid loops based on the operation of one or more shut-off valves 112, as also discussed in further detail below in fig. 15. In particular, the controller 120 may send one or more signals to the appropriate shut-off valve 112 to control the flow of cooling fluid through the purge heat exchanger 114, as discussed above.

In certain embodiments, as shown in fig. 10, the purge system 80 may include a refrigerant loop 172 configured to flow cooling refrigerant through the purge coil 116 to condense vapor refrigerant drawn from the condenser 34. In particular, the liquid pump 162 of the refrigerant loop 172 configured to pump liquid refrigerant may draw liquid refrigerant from the evaporator 48 through the conduit 174. In some embodiments, the liquid refrigerant drawn from the evaporator 38 may include a portion of vapor refrigerant. In other words, the liquid pump 162 may draw a two-phase mixture of vapor refrigerant and liquid refrigerant from the evaporator 38. Accordingly, in some embodiments, the purge system 80 may include a flash tank, such as the intermediate vessel 70 (fig. 4) disposed along the conduit 174 between the liquid pump 162 and the evaporator 38. To this end, the liquid refrigerant may be separated from the vapor refrigerant in the flash tank. Liquid refrigerant may be drawn from the flash tank by the liquid pump 162 along conduit 174 and vapor refrigerant may be directed from the flash tank to the outlet side of the evaporator 38. The liquid pump 162 of the refrigerant loop 172 may then pump liquid refrigerant through the purge coil 116 and back to the evaporator 38. Before reaching the cleaning coil 116, the liquid refrigerant may traverse one or more portions of the conduit 174 to which the thermoelectric assembly 82 is coupled. Specifically, as the liquid refrigerant flows through the conduit 174, the thermoelectric assembly 82 may remove heat from the liquid refrigerant, thereby cooling the liquid refrigerant to a subcooled state. In this manner, the refrigerant may remain in a liquid state as it flows through the purge coil 116, transfers heat to the mixture of refrigerant vapor and NCG, and back to the evaporator 38. Indeed, the liquid pump 162 of the refrigerant loop 172 may be a modified pump configured to pump refrigerant liquid.

Further, in certain embodiments, as shown in fig. 11, the purge system 80 may include a refrigerant loop 172 and an open fluid loop 165, both of which may flow a cooling fluid into the purge heat exchanger 114 to separate a mixture of refrigerant vapor and NCG drawn from the condenser 34 by condensing the refrigerant vapor in the mixture. Indeed, the refrigerant loop 172 may function as described above with reference to fig. 10, and the open fluid loop 165 may function as described above with reference to fig. 9. Further, as also discussed above, in certain embodiments, the refrigerant loop 172 and the open fluid loop 165 may flow cooling fluid through separate respective purge coils 116, or may flow cooling fluid through a single purge coil 116. In particular, the cleaning coil 116 may receive a mixture of fluids from separate fluid loops based on the operation of one or more shut-off valves 112 (shown in fig. 14 and 15). Specifically, the controller 120 may send one or more signals to the appropriate shut-off valve 112 to control the flow of cooling fluid through the purge heat exchanger 114.

Further, in all embodiments discussed herein, the purge system 80 may utilize the adsorption chamber 180 to remove NCG from the vapor compression system 14. For example, as discussed above, the vacuum pump 132 may remove gases from the cleaning chamber 118 that cleans the heat exchanger 114. In particular, in certain embodiments, the vacuum pump 132 may remove NCG and refrigerant vapor from the purge chamber 118. Therefore, the adsorption chamber 180 may remove a portion of the refrigerant vapor sucked by the vacuum pump 132 before discharging the NCG into the atmosphere. To illustrate, the vacuum pump 132 may pump a mixture (or "mixture") of NCG and refrigerant vapor through the conduit 182 to one or more of the adsorption chambers 180. As the mixture traverses one of the adsorbent chambers 180, the mixture may pass through the modifying material 184 of the adsorbent chamber 180 and, due to the properties of the modifying material 184 and the refrigerant vapor, the refrigerant vapor may be adsorbed or drawn into and/or onto the modifying material 184. For example, the electrochemical properties may facilitate adsorption, as described herein. Further, as the mixture traverses the adsorption chamber 180, the NCG may not be adsorbed into the modifying material 184, also due at least in part to the properties of the NCG and/or modifying material 184. Thus, the NCG may be vented to the atmosphere through the modified material 184 and on through the air outlet valve 186.

Since the modifying material 184 adsorbs the refrigerant, the modifying material 184 may eventually become saturated with the refrigerant and may no longer efficiently adsorb additional refrigerant. Accordingly, a heater 188, such as an immersion heater, an external cable heater, or a band heater, may be activated to provide thermal energy to the modification material 184 to heat the refrigerant. In this manner, the heater 188 will help the refrigerant overcome the bonding of the modifying material 184 such that the modifying material 184 releases the refrigerant in a vapor state. Once released from the modifying material 184, the refrigerant vapor may have a high pressure relative to the pressure within the evaporator 38 such that the refrigerant vapor flows to the evaporator 38 through the conduit 190.

In some embodiments, the shut-off valves 112 may allow the mixture to flow to only certain adsorbent chambers 180 at a time. In this manner, the adsorbent chamber 180 may continue to receive and filter the mixture, as described above. For example, the controller 120 may control the shut-off valve 112 to allow one or more particular ones of the adsorbent chambers 180 to filter the mixture. Once a particular adsorption chamber 180 becomes saturated with refrigerant, the controller 120 may stop the flow of the mixture to the particular adsorption chamber 180 and allow the mixture to flow to a different adsorption chamber 180. Once the controller 120 has stopped the flow to a particular adsorbent chamber 180, the controller may activate the heater 188 associated with the particular adsorbent chamber 180 to allow the refrigerant vapor to flow to the evaporator 38, as described above. In fact, different adsorbent chambers 180 may continue to filter the mixture as a particular adsorbent chamber 180 is heated. Once a particular adsorption chamber 180 is not sufficiently saturated with refrigerant, the controller 120 may once again activate one or more of the shut-off valves 112 to allow the mixture to flow to the particular adsorption chamber 180. To this end, the cleaning system 80 may include 1, 2, 3, 4, 5, 6, or any other suitable number of individual adsorbent chambers 180 to allow for continuous filtration of the mixture.

Further, in certain embodiments, as shown in fig. 12, the cleaning system 80 may include a closed fluid loop 160 and an open intermediate fluid loop 200, such as an open fluid loop. In particular, the closed fluid loop 160 may utilize a liquid pump 162 to flow a fluid, which may be water, saline, or a water/glycol mixture, through the conduit 201 and the wash coil 116. In practice, liquid pump 162 may be a modified pump configured to pump water, brine, or a water/glycol mixture. As liquid pump 162 pumps fluid of closed fluid loop 160 through conduit 201, first set of thermoelectric assemblies 82a may cool the fluid, as discussed above. In this manner, as the cooling fluid in closed fluid loop 160 flows through purge coil 116, the cooling fluid may separate a mixture of NCG and refrigerant vapor by condensing the refrigerant vapor within purge chamber 118, as discussed above.

Further, it should be noted that the cold side 86 of the first set of thermoelectric assemblies 82a may be coupled to a conduit 201, while the hot side 84 of the first set of thermoelectric assemblies 82a may be coupled to a conduit 202 configured for the flow of another cooling fluid. Specifically, the conduit 202 coupled to the hot side 84 of the first set of thermoelectric assemblies 82a may be part of the open intermediate fluid loop 200.

To illustrate, the liquid pump 162 of the open intermediate fluid loop 200 may draw fluid, which may be water, brine, a water/glycol mixture, or a combination thereof, from the supply line 60S of the cooling load 62 (fig. 3 and 4) through the conduit 204. In particular, in certain embodiments, the liquid pump 162 of the open intermediate fluid loop 200 may utilize fluid from a cooling system of a building, such as the building 12 (fig. 1). In practice, the fluid pumped from the supply line 60S may be water, brine, or a water/glycol mixture, and the liquid pump 162 of the open intermediate fluid loop 200 may be configured to pump water, brine, or a water/glycol mixture, respectively. The liquid pump 162 of the open intermediate fluid loop 200 may then pump fluid through the conduit 206 to which the second set of thermoelectric assemblies 82b may be coupled. The second set of thermoelectric assemblies 82b may remove heat from the fluid of the open intermediate fluid loop 200 as the fluid passes through the conduit 206. After passing through conduit 206, the fluid of open intermediate fluid loop 200 may pass through conduit 202. In particular, as mentioned above, the conduit 202 may be coupled to the hot side 84 of the first set of thermoelectric assemblies 82 a. In this manner, the fluid may absorb some heat from the hot side 84 of the thermoelectric assembly 82b as the fluid passes through the conduits 202 of the second set of thermoelectric assemblies 82 b.

In practice, the first set of thermoelectric assemblies 82a may replace the fan 100 (fig. 4 and 5) with cooling fluid flowing through the conduit 202 to increase the ability of the second thermoelectric assemblies 82a to cool the fluid in the closed fluid loop 160 to a lower temperature. For example, the cooling fluid flowing through the conduit 202 may be at a lower temperature than ambient air that the fan 100 might otherwise utilize to cool the hot side 84. Thus, by utilizing the cooling fluid within the conduit 202, the temperature differential between the cold side 86 and the hot side 84 may be reduced, thereby increasing the heat transfer efficiency of the cleaning system 80.

As the fluid of the open intermediate fluid loop 200 flows through the conduit 202 to cool the hot side 84 of the first set of thermoelectric assemblies 82a, the fluid may flow to the return line 60R via the conduit 208 to be cooled again within the evaporator 38, as discussed above.

In certain embodiments, as shown in fig. 13, the purge system 80 may utilize a refrigerant loop 172 to condense refrigerant vapor within the purge heat exchanger and an intercooling fluid loop 200 to cool a thermoelectric assembly 82a that is used to cool the fluid in the refrigerant loop 172 that is cooling the purge coil 116. For example, as previously discussed in fig. 10, the purge system 80 may utilize a refrigerant loop 172 to flow refrigerant from the evaporator 38 to a purge coil 116 that purges the heat exchanger 114 in order to separate a mixture of NCG and refrigerant vapor drawn from the condenser 34.

For example, the liquid pump 162 of the refrigerant loop 172 may pump refrigerant from the evaporator 38 through the conduit 210 and through the wash coil 116 of the wash heat exchanger 114. Further, as shown, the first set of thermoelectric assemblies 82a may be coupled to a conduit 210. Thus, the first set of thermoelectric modules 82a may cool or sub-cool the refrigerant as it flows through the conduit 210 to the wash coil 116. In particular, the thermoelectric module 82a may cool the refrigerant such that the refrigerant remains in a liquid state throughout the refrigerant loop 172.

Further, it should be noted that the cold side 86 of the first set of thermoelectric assemblies 82a may be coupled to a conduit 210, while the hot side 84 of the first set of thermoelectric assemblies 82a may be coupled to a conduit 212 configured for the flow of another cooling fluid. Specifically, the conduit 212 coupled to the hot side 84 of the first set of thermoelectric assemblies 82a may be part of the open intermediate fluid loop 200.

To illustrate, the liquid pump 162 of the open intermediate fluid loop 200 may draw fluid, which may be water, brine, a water/glycol mixture, or a combination thereof, from the supply line 60S of the cooling load 62 (fig. 3 and 4) through the conduit 214. In particular, in certain embodiments, the liquid pump 162 of the open intermediate fluid loop 200 may utilize fluid from a cooling system of a building, such as the building 12 (fig. 1). In practice, the fluid pumped from the supply line 60S may be water, brine, or a water/glycol mixture, and the liquid pump 162 of the open intermediate fluid loop 200 may be configured to pump water, brine, or a water/glycol mixture, respectively. The liquid pump 162 of the open intermediate fluid loop 200 may then pump fluid through the conduit 216 to which the second set of thermoelectric assemblies 82b may be coupled. The second set of thermoelectric assemblies 82b may remove heat from the fluid of the open intermediate fluid loop 200 as the fluid passes through the conduit 216. After passing through conduit 216, the fluid of open intermediate fluid loop 200 may pass through conduit 212. In particular, as mentioned above, the conduit 212 may be coupled to the hot side 84 of the first set of thermoelectric assemblies 82 a. In this manner, as the fluid of the intermediate fluid loop 200 passes through the conduits 212 of the first set of thermoelectric assemblies 82a, the fluid may absorb some heat from the hot side 84 of the first set of thermoelectric assemblies 82 a.

In practice, the first set of thermoelectric assemblies 82a may utilize a cooling fluid flowing through the conduit 212 in place of the fan 100 (fig. 4 and 5) to improve the heat removal capability of the second thermoelectric assemblies 82 a. For example, the cooling fluid flowing through the conduit 212 may be at a lower temperature than ambient air that the fan 100 might otherwise utilize to cool the hot side 84. Thus, by utilizing the cooling fluid within the conduit 212, the temperature differential between the cold side 86 and the hot side 84 may be reduced, thereby increasing the heat transfer efficiency of the cleaning system 80.

As the fluid of the open intermediate fluid loop 200 flows through the conduit 212 to cool the hot side 84 of the first set of thermoelectric assemblies 82a, the fluid may flow to the return line 60R via the conduit 220 to be cooled again within the evaporator 38, as discussed above.

As discussed above, the purge heat exchanger 114 may receive cooling fluid from more than one fluid loop, such as the closed fluid loop 160, the open fluid loop 165, and/or the refrigerant loop 172. In particular, the heat exchanger 114 may receive cooling fluid from two separate fluid loops. Thus, in certain embodiments, as shown in fig. 14, the purge heat exchanger 114 may include a first purge coil 116a that may be part of a first fluid loop 222a, and may also include a second purge coil 116b that may be part of a second fluid loop 222 b. Indeed, in certain embodiments, the first fluid loop 222a and the second fluid loop 222b may be part of the closed fluid loop 160, the open fluid loop 165, or the refrigerant loop 172. In particular, in the illustrated embodiment, the first cleaning coil 116a and the first fluid loop 222b may be separate from the second cleaning coil 116b and the second fluid loop 222. In such embodiments, the controller 120 may operate one or more of the shut-off valves 112 to flow cooling fluid through the first fluid loop 222a, the second fluid loop 222a, or both, to flow through the purge heat exchanger 114.

Further, in certain embodiments, as shown in fig. 15, the purge heat exchanger 114 may include a single purge coil 116c that may receive cooling fluid from the first fluid loop 222a, the second fluid loop 222b, or both. In practice, a single cleaning coil 116c may be part of the first fluid loop 222a, the second fluid loop 222b, or both. That is, the controller 120 may operate the appropriate shut-off valve 112 to flow cooling fluid from the first fluid loop 222a, the second fluid loop 222b, or both, through the single purge coil 116c of the purge heat exchanger 114.

Indeed, as discussed above with reference to fig. 14 and 15, the purge heat exchanger 114 may receive cooling fluid from two separate fluid circuits (such as the first fluid circuit 222a and the second fluid circuit 222 b). In certain embodiments, the first fluid loop 222a and the second fluid loop 222b may flow different types of fluids. For example, the first fluid loop 222a may use water as the cooling fluid, while the second fluid loop 222b may utilize brine, refrigerant, or a water/glycol mixture. In such an embodiment, the water within the first fluid loop 222a may have a first freezing temperature, and the brine, refrigerant, or water/glycol mixture within the second fluid loop 222b may have a second freezing temperature that is lower than the first freezing temperature. Thus, the fluid within the second fluid loop 222b may be cooled to a lower temperature than the fluid within the first fluid loop 222a before the fluid begins to solidify or freeze. Thus, in certain embodiments, the controller 120 may operate the shut-off valve 112 accordingly to utilize cooling fluid in only the first fluid circuit 222a, the second fluid circuit 222b, or both, depending on the type of cooling fluid and the amount of cooling that may be used to sufficiently condense the refrigerant vapor within the purge heat exchanger 114.

Further, it should be noted that the embodiments discussed herein with respect to fig. 7-13, and in particular the thermoelectric assembly 82, may be utilized if the vapor compression system 14 is operating or if the vapor compression system 14 is not operating. Still further, as shown in fig. 7-13, in some embodiments, the liquid pump 162 and/or the vacuum pump 132 may be powered by one or more motors 240, which may be any suitable motor. In some embodiments, the controller 120 may control the liquid pump 162 and/or the vacuum pump 132 by communicating with one or more motors 240. In particular, the controller 120 may operate the

pumps

162, 132 based on temperature data and/or pressure data obtained from one or more sensors 138 of the washing system 30. In some embodiments, one or more motors 240 may receive power from power source 90. Further, in some embodiments, controller 120 may control the amount of power sent from power supply 90 to thermoelectric assembly 82 to set the appropriate amount of heat removal. For example, in some embodiments, the controller 120 may reduce the amount of power sent to the thermoelectric assembly 82 to save on power costs or reduce the amount of heat removal performed by the thermoelectric assembly 82.

Accordingly, the present disclosure is directed to providing systems and methods for purging a low pressure HVAC system (e.g., chiller system, vapor compression system) of NCGs that may enter during operation. Specifically, the purging system may purge the HVAC system of NCG by utilizing a cooling fluid that has been cooled via the thermoelectric assembly. The disclosed embodiments enable HVAC systems to be purged of NCGs without the use of additional refrigerants that may have high GWPs. Further, it should also be understood that features of any embodiment discussed herein may be combined with any other embodiment or feature discussed herein.

Although only certain features and embodiments have been illustrated and described, many modifications and changes may occur to those skilled in the art (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters (e.g., temperatures, pressures, etc.), mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited in the claims. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention. Furthermore, in an effort to provide a concise description of the exemplary embodiments, all features of an actual implementation may not have been described (i.e., those unrelated to the presently contemplated best mode of carrying out the invention, or those unrelated to enabling the invention). It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure, without undue experimentation.

Claims

1. A heating, ventilation and air conditioning (HVAC) system comprising:

a refrigerant loop configured for flowing a refrigerant; and

a purging system configured for purging the HVAC system of non-condensable gases (NCGs), the purging system comprising:

a purge heat exchanger configured to receive a mixture comprising the NCG and the refrigerant, wherein the purge heat exchanger is configured to separate the NCG in the mixture from the refrigerant in the mixture with a non-refrigerant fluid; and

a thermoelectric assembly configured to remove heat from the non-refrigerant fluid.

2. The HVAC system of claim 1, wherein the non-refrigerant fluid comprises water, brine, a water/glycol mixture, or a combination thereof.

3. The HVAC system of claim 1, wherein the purge system comprises a closed fluid loop configured to flow the non-refrigerant fluid through a conduit and a purge coil of the purge heat exchanger, and wherein the thermoelectric assembly is coupled to the conduit and configured to remove heat from the non-refrigerant fluid as the non-refrigerant fluid flows through the conduit.

4. The HVAC system of claim 1, comprising:

a compressor disposed along the refrigerant loop and configured to circulate the refrigerant through the refrigerant loop;

an evaporator disposed along the refrigerant loop and configured for placing the refrigerant in heat exchange relationship with a first cooling fluid; and

a condenser disposed along the refrigerant loop and configured to place the refrigerant in heat exchange relationship with a second cooling fluid.

5. The HVAC system of claim 4, wherein the non-refrigerant fluid comprises a portion of the first cooling fluid, wherein the purging system comprises an open fluid loop configured for: drawing the non-refrigerant fluid from a flow path through which the first cooling fluid flows; flowing the non-refrigerant fluid through a conduit and a purge coil of the purge heat exchanger; and flowing the non-refrigerant fluid back to the flow path, and wherein the thermoelectric assembly is coupled to the conduit and configured to remove heat from the non-refrigerant fluid as the non-refrigerant fluid flows through the conduit.

6. The HVAC system of claim 4, wherein the non-refrigerant fluid comprises a first non-refrigerant fluid and the thermoelectric assembly is a first thermoelectric assembly, wherein the purge heat exchanger is further configured to separate the mixture with a second non-refrigerant fluid separate from the first non-refrigerant fluid, and wherein the purge system comprises a second thermoelectric assembly configured to remove heat from the second non-refrigerant fluid.

7. The HVAC system of claim 6, wherein the purge system comprises a closed fluid loop configured for flowing the first non-refrigerant fluid through a first conduit and a purge coil of the purge heat exchanger, wherein the first thermoelectric assembly is coupled to the first conduit and configured for removing heat from the first non-refrigerant fluid as the first non-refrigerant fluid flows through the first conduit, wherein the second non-refrigerant fluid comprises a portion of the first cooling fluid, wherein the purge system comprises an open fluid loop configured for: drawing the second non-refrigerant fluid from a flow path through which the first cooling fluid flows; flowing the second non-refrigerant fluid through a second conduit and a wash coil of the wash heat exchanger; and returning the second non-refrigerant fluid to the flow path, and wherein the second thermoelectric assembly is coupled to the second conduit and configured to remove heat from the second non-refrigerant fluid as the second non-refrigerant fluid flows through the second conduit.

8. The HVAC system of claim 7, wherein the purge coil comprises a first purge coil and a second purge coil, wherein the closed fluid loop comprises the first purge coil, and wherein the open fluid loop comprises the second purge coil.

9. The HVAC system of claim 7, wherein the purge coil comprises a single purge coil, wherein the closed fluid loop comprises the single purge coil, and wherein the open fluid loop comprises the single purge coil.

10. The HVAC system of claim 4, comprising a pump configured for: withdrawing the mixture from the condenser; increasing the pressure of the mixture; and delivering the mixture to the purge heat exchanger.

11. The HVAC system of claim 1, comprising a vacuum pump coupled to the purge heat exchanger, wherein the vacuum pump is configured to pump gas from the purge heat exchanger.

12. The HVAC system of claim 11, wherein the vacuum pump is configured to pump the mixture from the purge heat exchanger to an adsorption chamber configured to separate the NCG from the refrigerant.

13. A heating, ventilation and air conditioning (HVAC) system comprising:

a refrigerant loop;

a compressor disposed along the refrigerant loop and configured to circulate a refrigerant through the refrigerant loop;

an evaporator disposed along the refrigerant loop and configured for placing the refrigerant in heat exchange relationship with a first cooling fluid;

a condenser disposed along the refrigerant loop and configured for placing the refrigerant in heat exchange relationship with a second cooling fluid; and

a purge heat exchanger configured to separate a mixture drawn from the condenser with a first refrigerant stream of the refrigerant drawn from the evaporator and with a non-refrigerant fluid, wherein the mixture comprises the NCG drawn from the condenser and a second refrigerant stream of the refrigerant, and wherein the purge heat exchanger is configured to separate the NCG in the mixture from the second refrigerant stream in the mixture; and

a thermoelectric assembly configured to remove thermal energy from the first refrigerant flow and the non-refrigerant fluid.

14. The HVAC system of claim 13, wherein the non-refrigerant fluid comprises a portion of the first cooling fluid, and the purging system comprises:

a purge refrigerant loop configured for flowing the first refrigerant stream and comprising:

a first conduit and a cleaning coil of the cleaning heat exchanger; and

an open fluid loop configured for flowing the non-refrigerant fluid and comprising:

a second conduit and a cleaning coil of the cleaning heat exchanger.

15. The HVAC system of claim 14, wherein the thermoelectric assembly comprises a first thermoelectric assembly and a second thermoelectric assembly, wherein the first thermoelectric assembly is coupled to the first conduit and configured to remove heat from a first flow of refrigerant, and wherein the second thermoelectric assembly is coupled to the second conduit and configured to remove heat from the non-refrigerant fluid.

16. The HVAC system of claim 14, wherein the purge refrigerant loop comprises a refrigerant pump configured to pump the first refrigerant flow through the purge refrigerant loop, and wherein the open fluid loop comprises a non-refrigerant liquid pump configured to pump the non-refrigerant fluid through the open fluid loop.

17. The HVAC system of claim 14, wherein the purge coil comprises a first purge coil and a second purge coil, wherein the purge refrigerant loop comprises the first purge coil, and wherein the open fluid loop comprises the second purge coil.

18. The HVAC system of claim 14, wherein the purge coil comprises a single purge coil, wherein the purge refrigerant loop comprises the single purge coil, and wherein the open fluid loop comprises the single purge coil.

19. The HVAC system of claim 13, wherein the non-refrigerant fluid comprises water, brine, a water/glycol mixture, or a combination thereof.

20. A heating, ventilation and air conditioning (HVAC) system comprising:

a refrigerant loop;

a purge heat exchanger configured to receive a mixture comprising the NCG and the refrigerant, wherein the purge heat exchanger is configured to separate the NCG in the mixture from the refrigerant in the mixture with a cooling fluid in a cooling fluid loop; and

a thermoelectric assembly configured to cool the cooling fluid with an intermediate fluid in an open fluid loop.

21. The HVAC system of claim 20, wherein the thermoelectric assembly is a first thermoelectric assembly, and wherein the purging system comprises a second thermoelectric assembly configured to remove heat from the intermediate fluid of the open fluid loop.

22. The HVAC system of claim 20, wherein the cooling fluid loop is a closed fluid loop, and wherein the cooling fluid in the cooling fluid loop is a non-refrigerant fluid.

23. The HVAC system of claim 20, wherein the cooling fluid comprises water, brine, a water/glycol mixture, or a combination thereof.

24. The HVAC system of claim 20, wherein the cooling fluid in the cooling fluid loop comprises refrigerant drawn from the evaporator.

25. The HVAC system of claim 20, wherein the cooling fluid loop comprises a first conduit and a purge coil of the purge heat exchanger, wherein the open fluid loop comprises a second conduit, wherein the thermoelectric assembly is coupled to the first conduit at a first side of the thermoelectric assembly and to the second conduit at a second side of the thermoelectric assembly, wherein the thermoelectric assembly is configured to absorb heat from the cooling fluid via the first side of the thermoelectric assembly, and wherein the intermediate fluid is configured to absorb heat from the second side of the thermoelectric assembly.