Air conditioning unit with a leak detection inducer

Abstract

Air conditioning unit, including: a housing comprising a first chamber and a second chamber separated from the first chamber by a partition arranged in the housing, the housing having an air inlet and an air outlet; a coolant circuit which includes a compressor located in the first chamber; an airflow path extending through the second chamber, wherein the airflow path is arranged to direct an airflow from the air inlet to the air outlet, a blower arranged in the airflow path; a coolant leak detection system designed to detect a coolant leak within the housing; and an inducer arranged in the housing, wherein the inducer is configured to move air from the first chamber into the airflow path when the coolant leak is detected by the coolant leak detection system.

Description

AREA

[0001] This disclosure relates to air conditioning units used in heating, ventilating, air conditioning, and refrigeration ("HVACR") systems. More particularly, this disclosure relates to air conditioning units having an inducer for venting leaked refrigerant. GENERAL STATE OF THE ART

[0002] HVAC systems are generally used to heat, cool, and / or ventilate a conditioned space (e.g., an interior of a commercial or residential building, an interior of a refrigerated transport unit, or the like). An HVAC system may include an air conditioning unit for conditioning indoor air to provide climate control within the conditioned space. The air conditioning unit may include multiple chambers for accommodating components of the air conditioning unit. SUMMARY

[0003] This disclosure relates to air conditioning units used in heating, ventilating, air conditioning, and refrigeration ("HVACR") systems. More particularly, this disclosure relates to air conditioning units having an inducer for venting leaked refrigerant.

[0004] The air conditioning unit may be a heat pump operating in a heating mode or a cooling mode. During cooling mode, the conditioned air in a blower chamber is cooled by a heat exchanger acting as an evaporator. The air in the compressor chamber, located adjacent to the blower chamber, may be relatively hot because the compressor generates heat through its operation and / or the first heat exchanger releases heat through its operation as a condenser. In a heating mode, the second heat exchanger, acting as a condenser, heats the air in the blower chamber, and the air in the blower chamber may have a temperature that is generally higher than the air in the compressor chamber. Consequently, there is generally a temperature difference between the blower chamber and the compressor chamber in both operating modes.By restricting and controlling the airflow between the compressor and blower chambers, convective heat transfer is reduced or eliminated and the efficiency, capacity and performance of the air conditioning unit can be improved.

[0005] To restrict and control airflow between the blower chamber and the compressor chamber, each chamber is surrounded by tightly fitting plates that enclose the chambers, thus minimizing or reducing air loss between the two chambers. The compressor chamber, which has an enclosed volume, can also reduce noise transmission from compressor operation.

[0006] Refrigerant may leak from the refrigerant circuit, e.g., at the compressor, into a closed volume (e.g., the compression chamber). The accumulating refrigerant may be toxic and / or flammable. Leaked refrigerant may be drained to prevent a toxic or flammable amount of leaked refrigerant from accumulating. For example, refrigerants with relatively low toxicity and / or flammability (e.g., A2L refrigerant) can be vented by mixing the air containing leaked refrigerant with the intake and / or supply air of the air conditioning system. When mixed with the return and / or supply air, the leaked refrigerant is present at a low concentration that is harmless to humans and undetectable.By controlled venting the air into the blower chamber, any leaked refrigerant can be removed if a leak is detected, while the two chambers remain separated if no leak is detected to maintain the high efficiency of the air conditioning unit.

[0007] In one embodiment, the air conditioning unit comprises: a housing having a first chamber and a second chamber separated from the first chamber by a partition wall arranged in the housing, the housing having an air inlet and an air outlet. A refrigerant circuit has a compressor arranged in the first chamber. An air flow path extends through the second chamber. The air flow path is arranged to direct the air flow from the air inlet to the air outlet. A fan is arranged in the air flow path. A refrigerant leak detection system is arranged to detect a refrigerant leak within the housing; and an inducer is arranged in the housing. The inducer is arranged to move air from the first chamber into the air flow path upon detection of the refrigerant leak by the refrigerant leak detection system.

[0008] In one embodiment, the inducer is disposed on the partition wall and above an opening extending through the partition wall.

[0009] In one embodiment, the inducer is an inducer fan.

[0010] In one embodiment, the inducer is configured to move air through the partition in an activated mode.

[0011] In one embodiment, the inducer is configured to prevent airflow through the inducer in a deactivated mode.

[0012] In one embodiment, the inducer is configured to direct the air from the first chamber into the air flow path at a location in the air flow path at which the air flow path is conditioned.

[0013] In one embodiment, the air conditioning system includes an air duct extending from the inducer to the compressor to draw air from the vicinity of the compressor through the inducer into the air duct.

[0014] In one embodiment, the coolant leak detection system is configured to determine a coolant concentration within the housing. The inducer is configured to activate in response to the coolant concentration exceeding a predetermined value.

[0015] In one embodiment, the first chamber and the second chamber are enclosed by the housing and the partition wall.

[0016] A method relates to venting an air conditioning unit having a housing with a first chamber, a second chamber separated from the first chamber by a partition wall disposed in the housing, an air inlet, and an air outlet; and a refrigerant leak source disposed in the first chamber. The method includes directing airflow from the air inlet to the air outlet through the second chamber, preventing airflow between the first chamber and the second chamber; and moving air in the first chamber into the airflow path to disperse leaked refrigerant in the first chamber into the airflow path upon detecting a refrigerant leak.

[0017] Optionally, the method includes determining whether a concentration of the coolant in the first chamber exceeds a predetermined value; and activating the inducer to move the air in the first chamber into the airflow path. Optionally, the method includes, if it is determined that the concentration of the coolant does not exceed the predetermined value, preventing airflow between the first chamber and the second chamber.

[0018] In one embodiment, an HVAC system is configured to deliver conditioned air to a conditioned space. The HVAC system includes: a refrigerant circuit including a compressor, a first exchanger, a second exchanger, and an expander that are fluidly connected; a housing having a first chamber containing the compressor and a second chamber containing a blower, the housing having an air inlet and an air outlet; a partition wall disposed within the housing, the partition wall separating the first chamber and the second chamber; an airflow path extending through the second chamber, the airflow path configured to direct airflow from the air inlet to the air outlet; a refrigerant leak detection system configured to detect a refrigerant leak within the housing;and an inducer disposed in the housing, the inducer configured to move air in the first chamber into the air flow path upon detection of the coolant leak by the coolant leak detection system;

[0019] In one embodiment, the first heat exchanger is configured to condition the air and provide the conditioned air; and the first heat exchanger is disposed in the second chamber.

[0020] In one embodiment, the inducer is an inducer fan.

[0021] In one embodiment, the second heat exchanger is arranged in the second chamber.

[0022] In one embodiment, the coolant leak detection system is configured to determine a concentration of coolant within the housing and activate the inducer when the concentration exceeds a predetermined value.

[0023] In one embodiment, the inducer is disposed on the partition wall and above an opening extending through the partition wall. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic representation of one embodiment of a refrigerant circuit of an HVAC system. Fig. 2 is a perspective view of an embodiment of an air conditioning unit. Fig. 3 is a perspective view of the air conditioning unit in Fig. 2, wherein a top side is omitted and front sides are partially omitted, according to one embodiment. Fig. 4 is a schematic plan view of the air conditioning unit in Fig. 2, with the top side omitted, according to one embodiment. Fig. 5 is a block flow diagram of a method for venting an air conditioning unit. Fig. Figure 6 is a block flow diagram for operating an air conditioning unit. Like reference numerals represent like features. DETAILED DESCRIPTION

[0024] This disclosure relates to air conditioning units used in heating, ventilating, air conditioning, and refrigeration ("HVACR") systems. More particularly, this disclosure relates to air conditioning units having an inducer for venting leaked refrigerant.

[0025] Fig. 1 is a schematic representation of one embodiment of a cooling circuit 5 in a heating, ventilation, air conditioning, and refrigeration (HVAC) system 1. In one embodiment, the HVAC system 1 may be an industrial or residential HVAC system 1 configured to air condition the interior of a building (e.g., office space, residential buildings, or the like).

[0026] The refrigeration circuit 5 includes a compressor 10, a condenser 20, an expander 30, and an evaporator 40. In one embodiment, the refrigeration circuit 5 may be modified to include additional components. For example, in one embodiment, the refrigeration circuit 5 may include an economizer heat exchanger, one or more flow control devices, a receiver tank, a dryer, a liquid suction heat exchanger, or the like. The components of the refrigeration circuit 5 are fluidly connected. Fig. 1, dotted lines are provided for ease of understanding to indicate that fluid flows through some components (e.g., the compressor 10, the condenser 20, the evaporator 40) and are not intended to specify a specific path in the individual components.

[0027] The coolant circuit 5 may be configured as a cooling system (e.g., a fluid cooler of an HVAC system, an air conditioning system, or the like) that can be operated in a cooling mode, and / or the coolant circuit 5 may be configured to be operated as a heat pump system that can run in a cooling mode and a heating mode.

[0028] The cooling circuit 5 uses known principles of gas compression and cooling circuitry. The cooling circuit can be configured to heat or cool a process fluid (e.g., water, air, or the like). In one embodiment, the cooling circuit 5 can be a chiller that cools a process fluid, such as water or the like. In one embodiment, the cooling circuit 5 can be an air conditioning system and / or a heat pump that cools and / or heats a process fluid, such as air or the like. In one embodiment, the coolant circuit 5 can be a heat pump configured to supply heated or cooled air to the conditioned space.

[0029] During operation of the refrigeration cycle 5, a working fluid (containing, for example, refrigerant, a refrigerant mixture, or the like) flows into the compressor 10 from the evaporator 40 in a gaseous state at a relatively low pressure. The compressor 10 compresses the gas to a high-pressure state, which also heats the gas. After being compressed, the gas flows from the compressor 10 to the condenser 20 at a relatively high pressure and high temperature. In addition to the working fluid flowing through the condenser 20, a first fluid PF1 (e.g., outside air, external water, cooling water, heating water, or the like) also flows separately through the condenser 20. The first process fluid absorbs heat from the working fluid as the first process fluid PF1 flows through the condenser 20, which cools the working fluid as it flows through the condenser. The working fluid condenses into liquid and then flows into the expander 30.The expander 30 enables the expansion of the working fluid, thereby converting the working fluid into a mixed vapor and liquid state.

[0030] An "expander," as described herein, may also refer to an expansion device. In one embodiment, the expander may be an expansion valve, an expansion plate, an expansion vessel, an orifice, or the like, or any other such type of expansion mechanism. It should be noted that the expander may be any type of expander used in the art for expanding a working fluid to cause a reduction in the pressure and temperature of the gaseous working fluid. The relatively low-temperature vapor / liquid working fluid then flows into the evaporator 40. A second process fluid PF2 (e.g., air, chiller fluid, water, or the like) also flows through the evaporator 40. The working fluid absorbs heat from the second process fluid PF2 as it flows through the evaporator 40, cooling the second process fluid PF2 as it flows through the evaporator 40.When the working fluid absorbs heat, the working fluid evaporates into steam. The working fluid then returns from the evaporator 40 to the compressor 10. The process described above continues while the refrigeration circuit 5 is operated, for example, in a cooling mode.

[0031] Fig. Figure 2 is a perspective view of an air conditioning unit 100 according to one embodiment. In one embodiment, the air conditioning unit 100 serves a heating, ventilation, air conditioning, and refrigeration system 101.

[0032] The air conditioning unit 100 includes a housing 110 to provide structural support and / or contain components therein. The housing 110 includes a plurality of sides 112, 114, 116, 118, 120, 122 (the sides 116, 120, 122 are shown in Fig. 2). The sides may also be referred to as top 112, left side 114, right side 116, front 118, back 120, and bottom 122. The components of the air conditioning unit 100 are disposed within the housing 110. In one embodiment, the housing 110 is the outer casing of the air conditioning unit 100. In one embodiment, the air conditioning unit 100 may also be referred to as an air handling unit, a packaged unit, a heat pump unit, or the like.

[0033] The air conditioning unit 100 has an inlet 102 and an outlet 104 formed in the housing 110. For example, the inlet 102 is formed in a first side 120 (e.g., rear) of the housing 110, and the outlet 104 is formed in a second side 118 (e.g., front) of the housing 110. Air is drawn into the air conditioning unit 100 through the inlet 102, conditioned within the air conditioning unit 100 (e.g., heated, cooled, or the like), and discharged (as conditioned air) from the outlet 104. It should be noted that the inlet 102 and the outlet 104 may be formed in different sides 112, 116, 118, 120, 122 of the housing 110 than in Fig. 3 shown.

[0034] Fig. 3 is a perspective view of the air conditioning unit 100 with the top 118 omitted and the left side 114 and the front 118 partially omitted, according to one embodiment. The air conditioning unit 100 includes a refrigerant circuit 108 that operates to condition the air flowing through the air conditioning unit 100 (e.g., the refrigerant in the refrigerant circuit 108 is used to heat and / or cool the air). For example, the refrigerant circuit 108 may be the refrigerant circuit 5 in Fig. 1. The coolant circuit 108 can be arranged as above with respect to the coolant circuit 5 in Fig. 1 described.

[0035] As in Fig. 3, the air conditioning unit 100 includes a compressor 130, a first heat exchanger 132, an expander 134, and a second heat exchanger 136, which are fluidly connected (e.g., in series). The coolant circuit 108 includes the compressor 130, the first heat exchanger 132, the expander 134, and the second heat exchanger 136 (e.g., these are components of the coolant circuit 108). The compressor 130, the expander 134, the first heat exchanger 135, and the second heat exchanger 136 form a coolant circuit (e.g., coolant circuit 5 in Fig. 1).

[0036] In one embodiment, the coolant circuit may be reversible (e.g., with switching valve(s) to switch between operation in a cooling mode and a heating mode). In the cooling mode, the first heat exchanger 132 may be a heat exchanger operating as an evaporator configured to evaporate the coolant to cool supply air 210, and the second heat exchanger 136 may be a heat exchanger operating as a condenser configured to cool and condense the coolant (e.g., partially condense, fully condense) (e.g., the coolant is Fig. 3 cooled with water). It is understood that the supply air 210 may be recirculated air from the conditioned space, fresh air from outside the conditioned space (e.g., outside air), a combination thereof, or the like. In the heating mode, the first heat exchanger 132 may be operated as a condenser configured to heat the supply air 210, and the second heat exchanger 136 may be operated as an evaporator. The flow of the air 210 through the housing 110 is in Fig. 3 shown by dashed arrows.

[0037] Coolant lines (e.g. pipes, hoses and the like) between different components in the coolant circuit 108 in Fig. 3 (e.g., between the compressor 130 and the heat exchangers 132, 136, between the first heat exchanger 132 and the expander 134) are shown simplified as dashed arrows for illustrative purposes. The process fluid inlet and outlet lines for the second heat exchanger 136 (e.g., for water supply and disposal of the second heat exchanger 136 in Fig. 3) are in Fig. 3 is also omitted. For example, the dashed arrows indicate a direction in which the coolant flows when the coolant circuit 108 is operated in a cooling mode.

[0038] The housing 110 includes a plurality of chambers 124, 126. For example, each chamber 124, 126 is a different enclosed volume disposed within the housing 110. The chambers 124, 126 are each defined by the housing 110 (e.g., at least partially defined by the sides 112, 114, 116, 118, 120, 122 of the housing 110). As shown in Fig. As shown in Figure 3, the housing 110 has a first chamber 124 and a second chamber 126. The first chamber 124 is disposed adjacent to the second chamber 126.

[0039] The air conditioning unit 100 has a partition wall 128 arranged within the housing 110. The first chamber 124 and the second chamber 126 are separated from each other within the housing 110 by the partition wall 128. As shown in Fig. 3, the second chamber 126 is adjacent to the first chamber 124. In the illustrated embodiment, the first chamber 124 and the second chamber 126 are disposed on opposite surfaces of the partition wall 128. It should be understood that the housing 100 may have additional chambers or volumes disposed therein. It should also be noted that the chambers 124, 126 may be further subdivided into smaller volumes in some embodiments.

[0040] The partition wall 128 is configured to restrict and control airflow from the first chamber 124 to the second chamber 126. For example, the air in the first chamber 124 may be heated by the operation of the compressor 130. By restricting airflow into the second chamber, convective heat exchange between the first chamber 124 and the second chamber 126 may be reduced or eliminated. In one embodiment, the partition wall 128 may be configured to extend to and / or be coupled to the sides 112, 118, 120, and 122 of the housing 110.

[0041] The first chamber 124 may be a chamber within the housing 110 that contains the compressor 130 and / or the second heat exchanger 136. In the illustrated embodiment, the first chamber 124 contains the compressor 130 (e.g., the compressor 130 is disposed within the first chamber 124) and may be referred to as a compressor chamber. In one embodiment, the first chamber 124 may be used to thermally isolate a component that is different from or in addition to the compressor 130 (e.g., the second heat exchanger 136, an economizer heat exchanger in the coolant circuit 108, or the like). As shown in Fig. 3, the second heat exchanger 136 may also be arranged in the first chamber 124. As shown in Fig. 3, the first chamber 124 may be provided / defined by the partition 128 and multiple sides of the housing 110 (e.g., by the partition 128 and the sides 112, 114, 118, 120, 122).

[0042] The air conditioning unit 100 includes the fan 138, which directs the air to flow through the housing 110 from the inlet 102 to the outlet 104. The second chamber 126 may include the fan 138 (e.g., the fan 138 is disposed within the second chamber 126) and may be referred to as a fan chamber. As shown in Fig. 3, the first heat exchanger 132 may be arranged in the second chamber 126. As shown in Fig. 3, the second chamber 126 may be provided / defined by the partition wall 128 and a plurality of the sides of the enclosure 110 (e.g., by the partition wall 128 and the sides 112, 116, 118, 120, 122). The second chamber 126 may be a chamber within the enclosure 110 that includes an air flow path 200 for receiving and conditioning the supply air 210 via the first heat exchanger 132 and for discharging the conditioned air 250. The conditioned air 250 may be directed into the conditioned space. In one embodiment, the second chamber 126 may be a chamber within the air conditioning unit 100 that includes the first heat exchanger 132, the blower 138, and the like.

[0043] The blower 138 is included in the air conditioning unit 100 to direct air through the housing 110 via the air inlet 102 and the air outlet 104. The blower 138 is disposed in the second chamber 126. In one embodiment, the blower 138 may also direct air through a system of ducts (not shown) to deliver the conditioned air 250 to the conditioned space and / or draw air (e.g., as supply air 210) into the air conditioning unit 100 for conditioning. Operation of the blower 138 allows the air 210 to flow through the airflow path 200. The fan 138 is configured to draw air into the housing 110 through the air inlet 102 and to exhaust the air (after being conditioned) from the housing 110 through the outlet 104. The inlet 102 and / or the outlet 104 may be openings in the housing 110.In the flow path 200, the supply air 210 flows through the first heat exchanger 132 after flowing through the inlet 102 into the housing 110. In a cooling mode, the coolant and the supply air 210 exchange heat in the first heat exchanger 132 (without physical mixing), while the coolant and the air each flow separately through the first heat exchanger 132, heating (e.g., evaporating) the coolant and cooling the supply air 210. The conditioned (e.g., cooled) air is then drawn into the fan 138 and discharged through the outlet 104 of the air conditioning unit 100. The air inlet 102 and the air outlet 104 may be an inlet and an outlet of the second chamber 126.

[0044] As in Fig. 3, the second heat exchanger 136 may be disposed within the first chamber 124. A process fluid (e.g., air, water, or the like) and the coolant exchange heat energy within the second heat exchanger 136 without physically mixing. In a cooling mode, the second heat exchanger 136 operates as a condenser configured to cool the coolant and condense it from the vapor to the liquid phase (e.g., to at least partially condense the coolant, to completely condense the coolant). It is understood that in the cooling mode, the coolant at a relatively high temperature releases heat energy to the air, water, or the like stream. In one embodiment, the heat energy released by the compressor 130 may be configured to be exchanged with the air, water, or the like stream, thereby removing heat within the first chamber 124.

[0045] In Fig. 3, the second heat exchanger 136 is a coaxial coil heat exchanger configured to heat / cool (e.g., cool / heat the coolant) the coolant using a fluid (e.g., water, antifreeze, brine, methanol, a combination thereof, or the like). It should be noted that in other embodiments, the second heat exchanger 136 may be a different type of heat exchanger. In one embodiment, the second heat exchanger 136 may be located outside the air conditioning unit 100. For example, the second heat exchanger 136 may be in the form of an evaporative condenser located remotely from the air conditioning unit 100 (e.g., a cooling tower cooling coolant from multiple air conditioning units, a remote air-cooled condenser, or the like).

[0046] An inducer 150 is included in the air conditioning unit 100 and is configured to control the air flow between the first chamber 124 and the second chamber 126, as described below with respect to Fig. 4 is explained in more detail.

[0047] The conditioned air in the second chamber 126 is assumed to be relatively cold during the cooling mode. The air in the first chamber 124 may be relatively hot because the compressor 130 generates heat through its operation and / or the second heat exchanger 136 rejects heat through its operation as a condenser. In a cooling mode, the compressor 130 and / or the second heat exchanger 136 heat the air in the first chamber 124 such that the first chamber 124 is generally at a higher temperature than the second chamber 126, where the first heat exchanger 132 absorbs heat energy, thereby cooling the air flowing through it. By limiting and controlling convective heat transfer (e.g., through air currents) between the first chamber 124 and the second chamber 126, the efficiency, capacity, and performance of the air conditioning unit 100 in the heating and / or cooling modes may be improved.

[0048] To restrict and control airflow between the first chamber 124 and the second chamber 126, the first chamber 124 and the second chamber 126 are enclosed such that panels (e.g., the housing 110, the sidewalls, the partition 128) fit together to form the first chamber 124 and the second chamber 126, respectively, and such that air loss between the two chambers 124, 126 is negligible. For example, the first chamber 124 may be sufficiently airtight to limit or prevent flow through an inducer 150 that is turned off and / or the partition 128 (e.g., sufficiently airtight from the external environment, sufficiently airtight within the housing 110 along the second chamber 126). For example, when the inducer 150 in the housing 110 is turned off, a pressure drop during suction from the second chamber 126 causes little to no air to flow from the first chamber 124 into the second chamber 126.When the inducer 150 in the housing 110 is switched on, air is drawn from the first chamber 124, causing air to flow from the first chamber 124 through the opening 129 and the inducer 150 of the partition 128 into the second chamber 126. The air movement between the first chamber 124 and the second chamber 126 is controlled, e.g., by switching the air valve 150 on or off.

[0049] It is understood that leaked refrigerant is vented to prevent a toxic or flammable amount of leaked refrigerant from accumulating. Because the first chamber 124 is closed, venting can be provided to reduce and eliminate the risk of toxic substances and / or fire. Refrigerant in a relatively low concentration may be harmless and undetectable to humans, so by venting into the second chamber 126 and venting the leaked refrigerant into the airflow path 200 and mixing it with a large volume of air, the leaked refrigerant that has accumulated in the air conditioning unit 100 can be effectively removed without affecting the occupants in the conditioned space.

[0050] The air conditioning unit 100 includes a refrigerant leak detection system 191. The refrigerant leak detection system 191 is configured to detect a refrigerant leak within the housing 110. The refrigerant leak detection system 191 may include one or more sensors 192A, 192B. The one or more sensors 192A, 192B are leak detection sensors. Leak detection sensors may include, for example, but not exclusively, one or more concentration sensors, power and / or operation sensors, or a combination thereof.

[0051] As in Fig. 3, the sensor(s) 192A, 192B may include a concentration sensor(s) configured to detect coolant in the air. A concentration sensor may be configured to detect the concentration of coolant directly (e.g., by measuring the coolant concentration in the air) or indirectly (e.g., by measuring the oxygen concentration in the air, where a decrease in the oxygen concentration indicates a corresponding amount of coolant in the air).

[0052] In the illustrated embodiment, the sensor(s) 192A, 192B may be concentration sensors configured to detect coolant within the housing 110 (e.g., to detect leaked coolant). The concentration sensor(s) 192A, 192B include a first coolant sensor 192A located within the compressor chamber 124. The concentration sensor(s) 192A, 192B may also include a second concentration sensor 192B located within the blower chamber 126. In one embodiment, the concentration sensor(s) 192A, 192B may be located closer to the floor than to the ceiling of the compressor chamber 124.

[0053] In another embodiment, the refrigerant leak detection system 191 may be configured to detect a refrigerant leak based on the operation of the refrigerant circuit. For example, a decrease in the performance (e.g., efficiency) of the conditioning system by the air conditioning system may be used to indicate a refrigerant leak. In such embodiments, the sensor(s) 192A, 192B may include one or more power sensors, temperature sensors, pressure sensors, current sensors, flow sensors, valve position sensors, or the like to detect the performance of the conditioning system of the refrigerant circuit, which may indicate a refrigerant leak.

[0054] The refrigerant leak detection system 191 may be configured to detect a refrigerant leak when the (detected) amount of detected refrigerant is above a predetermined minimum concentration (e.g., at or above a lower flammability level or the like). During operation of the blower 138, refrigerant is drawn from the compressor chamber 124 into the blower chamber 126, which is then discharged from the air conditioning unit 100 through the outlet 104.

[0055] When a refrigerant leak is detected, the controller 190 turns on the inducer 150. The inducer 150 fluidly connects the first chamber 124 to the second chamber 126 and draws the air in the first chamber, containing leaked refrigerant, into the airflow path 200 to disperse it into the conditioned air 250. During operation of the blower 138, refrigerant is drawn from the first chamber 124 into the second chamber 126, which is then exhausted from the air conditioning unit 100 through the outlet 104. When a refrigerant leak is detected, the controller 190 may also be configured to turn on the blower 138 (e.g., if the blower 138 is not currently operating).

[0056] The air conditioning unit 100 may include a controller 190 that controls the operation of the inducer 150. In one embodiment, the inducer 150 may be an aspirator or the like. In one embodiment, the controller 190 may be the controller of the air conditioning unit 100. In one embodiment, the controller 190 may be the controller of the refrigerant leak detection system 191. In another embodiment, the controller may be a separate controller dedicated to the operation of the inducer 150.

[0057] A controller 190 may be included in the air conditioning unit 100 for controlling the inducer 150, operating one or more sensors 192, and / or the like. The controller 190 may be disposed on the housing 110. In one embodiment, the controller 190 may be the controller of the air conditioning unit 100. In one embodiment, the controller 190 may be a controller of the refrigerant leak detection system 191. In another embodiment, the controller may be a separate controller dedicated to operating the inducer 150.

[0058] The controller 190 may also be configured to maintain operation of the blower 138 and / or the inducer 150 for a predetermined period of time. For example, the predetermined period of time may provide for venting of the chambers 124, 126 in accordance with UL 60335-2-40, Section GG.4 (4th Edition).

[0059] In one embodiment, the controller 190 may also be configured to maintain operation of the fan 138 for a predetermined period of time (e.g., for at least 5 minutes, for at least 10 minutes, or the like). In one embodiment, the fan 138 is maintained for the predetermined period of time after the concentration of the coolant (e.g., as sensed by each of the sensors 192A, 192B via the sensor(s) 192A, 192B) is at or below the predetermined minimum concentration.

[0060] In one embodiment, the controller 190 may also be configured to maintain operation of the inducer 150 for a predetermined period of time (e.g., for at least 5 minutes, for at least 10 minutes, or the like). In one embodiment, the inducer 150 is maintained for the predetermined period of time after the concentration of the coolant (e.g., as sensed by each of the sensors 192A, 192B via the sensor(s) 192A, 192B) is at or below the predetermined minimum concentration.

[0061] The controller 190 may be configured to turn off the inducer 150 after the coolant is no longer detected, is detected below the predetermined concentration, and / or after the predetermined period of time. In one embodiment, the opening 129 and / or the inducer 150 disposed on the opening 129 are so small that when the inducer is turned off, the amount of airflow through the partition 128 past the inducer 150 may be negligible. In one embodiment, the opening 129 may have a width of 10 inches or less. In one embodiment, the opening 129 may have a width of 6 inches or less. In one embodiment, the opening 129 may have a width of 4 inches or less. In one embodiment, the housing 110 may include one or more vents 127 disposed along the first chamber 124.The vent(s) 127 may allow air to flow into the first chamber 124 when air is drawn from the first chamber 124 via the inducer 150. In one example, the negative pressure caused by the drawing by the inducer 150 may cause the vent(s) 127 to open (e.g., move from closed to open).

[0062] While the air conditioning unit 100 illustrated in the drawing is a horizontal unit whose bottom 122 is disposed on a support structure, floor, roof, or the like, the first chamber 124 and the second chamber 126 are arranged side by side. However, embodiments may include vertical units such that the first chamber 124 and the second chamber 126 are stacked on top of each other, or other arrangements.

[0063] Fig. 4 is a schematic plan view of the air conditioning unit in Fig. 2, with the top side omitted, according to one embodiment.

[0064] As in Fig. 4, the inducer 150 can be arranged on the partition 128 and over an opening 129 (in Fig. 3) may be mounted on the partition wall 128. The inducer 150 has an activated mode and a deactivated mode. In the deactivated mode, the inducer 150 blocks / prevents flow through the inducer 150. In an activated mode, the inducer 150 may allow air 220 to flow from the first chamber 124 and the second chamber 126 such that the air 200 in the first chamber 124 is moved into the second chamber 126 to vent it. Air outside the air conditioning unit 100 may be drawn through, for example, panel gaps or vent slots 127 (shown in Fig. 3) on the housing 110 to renew the air in the first chamber 124. In one embodiment, the inducer 150 may be an inducer fan. The inducer fan may have one or more blades 152 such that when the inducer fan is turned on, the blades 152 rotate to force air through the inducer 150. When the inducer is turned on, the blades 152 are stationary and prevent airflow 220 through the inducer. In one embodiment, an air channel 154 extends from the partition wall 128 toward a coolant leak source. The air duct 154 may be a ducting structure (e.g., a cylindrical or rectangular tube) having a first opening at a first end located at the partition wall 128, above the opening 129, and / or above the inlet side of the inducer 150. A second end of the tubular structure of the air duct 154 is located at the coolant leak source.When the inducer 150 is activated, the inducer 150 can draw air near the coolant leak into the air passage 154, creating an airflow 220 through the partition wall 128. The air near the coolant leak source typically has a higher concentration of leaked coolant. With the air passage 154 present, the inducer 150 draws air near the coolant leak source and more effectively removes leaked coolant from the first chamber 124. In one embodiment, the coolant leak source is the compressor 130.

[0065] Fig. 5 is a block flow diagram of a method for venting an air conditioning unit.

[0066] For example, the method 1000 for venting the air conditioning unit 100 in Fig. 2 - 4 may be applied. Method 1000 may be applied by controller 190 of air conditioning unit 100. Method 1000 begins at 1010.

[0067] At 1010, air is directed through a blower plenum (e.g., second plenum 126) of a housing (e.g., housing 110) of the air conditioning unit. Directing the air (e.g., supply air 200) at 1010 may include directing the air to flow through a heat exchanger (e.g., first heat exchanger 132) to condition the air. The air may be conditioned (e.g., heated or cooled) by coolant as the supply air flows through the heat exchanger. Optionally, the supply air flows through the heat exchanger into the second plenum. Method 1000 then proceeds to 1020.

[0068] At 1020, a refrigerant leak detection system (e.g., refrigerant leak detection system 1010) detects refrigerant within the enclosure of the air conditioning unit. The refrigerant leak detection at 1020 may be based on one or more of the following: air conditioning system performance (e.g., detected conditioning performance by the air conditioning system), sensing the concentration of refrigerant in the air (e.g., directly or indirectly), and the like. The refrigerant leak detection system may include one or more refrigerant leak sensors (e.g., sensor(s) 192A, 192B). A refrigerant leak sensor may be, for example, but not limited to, a concentration sensor, a power sensor, or the like. For example, detecting the leaked refrigerant at 1020 may include detecting a refrigerant concentration within the enclosure (e.g., a concentration of refrigerant in the air) at 1022 with one or more concentration sensors.Sensing at 1022 may include sensing, with a concentration sensor (e.g., first sensor 192A), a concentration of the coolant in a first chamber within the housing (e.g., first chamber 124, a compressor chamber). Sensing at 1022 may include sensing, with a concentration sensor (e.g., second sensor 192B), a concentration of the coolant in the second chamber (e.g., second chamber 126, the blower chamber) within the housing.

[0069] For example, detecting the leaked refrigerant at 1020 may include detecting a performance of the air conditioning unit using one or more performance sensors. Detecting the performance of the air conditioning unit may include detecting one or more operating conditions of the air conditioning unit using one or more performance sensors. Operating conditions may include, but are not limited to, supply air temperature, conditioned air outlet temperature, compressor outlet pressure, refrigerant temperature(s) (e.g., refrigerant inlet and / or outlet temperature(s) at one or more components of refrigerant circuit 108), valve position (e.g., position of expander 134), or the like.

[0070] Detecting a coolant leak at 1020 may also include comparing the determined coolant concentration (e.g., detected at 1022) to a predetermined minimum threshold at 1024. For example, the coolant leak is detected at 1020 if a determined coolant concentration is at or above the predetermined minimum threshold. For example, if a determined coolant concentration is below the predetermined minimum threshold, no coolant leak is detected. Method 1000 may then proceed to 1030.

[0071] At 1030, an inducer (e.g., inducer 150) is activated in response to the detection of leaked coolant. Opening the inducer at 1030 is configured to vent at least the first chamber within the housing.

[0072] The fan (e.g., fan 138) may not be operating when leaking coolant is detected. In this case, method 1030 may include activating (e.g., turning on) the fan at 1010 in response to detecting the leaked coolant, in addition to or alternatively to 1010.

[0073] It will be appreciated that the method 1000 may be modified to include features as described above with respect to the air conditioning unit 100 in Fig. 1-4. For example, method 1000 may include a first mode (e.g., a heating or cooling mode) including 1010 for operation to heat or cool the air, and a second mode including 1020 and 1030 for venting the blower chamber in response to a detected coolant leak (e.g., a coolant leak vent mode).

[0074] Fig. 6 is a block flow diagram of a method 1200 for venting an air conditioning unit. For example, the method 1200 for venting the air conditioning unit 100 in Fig. 2 - 4 may be applied. Method 1200 may be applied by controller 190 of air conditioning unit 100. Method 1200 begins at 1210.

[0075] At 1210, the air conditioning unit is operating normally. For example, at 1210, the operation of the air conditioning unit is not modified / changed based on detecting a refrigerant leak. Normal operation may include, for example, operation in a conditioning mode (e.g., a heating mode, a cooling mode, or the like), a venting mode, an off mode, or the like. In the conditioning mode, air is drawn into the air conditioning unit, conditioned within the air conditioning unit, and the conditioned air is exhausted from the air conditioning unit (e.g., as described for the air conditioning unit 100 in the Fig. 2-4). In a vent mode, air is drawn into the air conditioning unit and then released without being conditioned. In an off mode, the air conditioning system is turned off (e.g., when no air conditioning or ventilation is currently required). Method 1200 then proceeds to 1220.

[0076] At 1220, the air conditioning unit detects a refrigerant leak within a housing (e.g., housing 110) of the air conditioning unit. For example, a refrigerant detection system (e.g., refrigerant detection system 191) detects a refrigerant leak. The refrigerant leak detection 1220 in Fig. 6, the coolant leak detection 1020 can be Fig. 5, as previously explained. If no refrigerant leak is detected at 1220, method 1200 returns to 1210 (e.g., the air conditioning unit continues normal operation). If a refrigerant leak is detected at 1220, method 1200 proceeds to 1230.

[0077] At 1230, if a fan (e.g., fan 138) of the air conditioning unit is not active (e.g., the fan is off / not currently operating), method 1200 proceeds to 1235. At 1235, the fan is enabled, and method 1200 then proceeds to 1240. At 1230, if the fan is active (e.g., already operating to force air through the enclosure), method 1200 proceeds from 1230 to 1240.

[0078] At 1240, a compressor (e.g., compressor 130) of the air conditioning unit is deactivated. For example, deactivating compressor 1240 may include preventing operation of compressor 1240 (e.g., stopping current operation and preventing future operation while refrigerant is still being sensed). For example, deactivating compressor 1240 may consist of no longer supplying electrical power to compressor 1240. Method 1200 then proceeds to 1250. At 1250, an inducer (e.g., inducer 150) of the air conditioning unit is activated (e.g., turned on, placed in the activated mode). Activating the inducer at 1250 in Fig. 6 can activate the inducer at 1030 in Fig. 5, as explained above. Method 1200 then proceeds to 1260.

[0079] At 1260, the air conditioning unit detects the refrigerant leak. For example, at 1260, it is determined whether the enclosure has been vented such that the refrigerant leak is no longer detected. The detection of the refrigerant leak at 1260 may be a continuation of the same refrigerant leak detection performed at 1220 (e.g., the refrigerant leak detection continues concurrently with 1230-1250). If the refrigerant leak continues to be detected at 1260, method 1200 continues detecting at 1260. If the refrigerant leak is not detected at 1260, method 1200 proceeds to 1270. For example, method 1200 does not proceed from 1260 to 1270 until the refrigerant leak is no longer detected.

[0080] At 1270, after a predetermined period of time has elapsed since no coolant leak was detected, method 1200 proceeds to 1280. If a coolant leak is detected during the period at 1270 (after no coolant leak was detected), method 1200 may return to 1260.

[0081] At 1280, the inducer is deactivated (e.g., turned off, placed in deactivated mode). Method 1200 then returns to 1210. At 1210, the air conditioning unit is operated normally. For example, the air conditioning unit may return to the same operation as before a refrigerant leak was detected at 1220 (e.g., before 1230). The air conditioning unit may change operation after detecting a refrigerant leak (e.g., transition to a modified normal operation). It is understood that method 1200 in Fig. 6 can be modified to meet the requirements set out herein for the air conditioning unit in Fig. 2 - 4 and / or for the procedure 1000 in Fig. 5. It should also be noted that the method 1200 in Fig. 6 may be modified to omit or combine one or more of the methods of blocks 1220-1280, as in Fig. 6 shown.

[0082] Aspects: Please note that in the following, each of the aspects 1 - 10 can be combined with each of the aspects 11 - 18 and each of the aspects 11 - 12 can be combined with each of the aspects 13 - 18. Aspect 1. Air conditioning unit comprising: a housing having a first chamber and a second chamber separated from the first chamber by a partition disposed in the housing, the housing having an air inlet and an air outlet; a refrigerant circuit having a compressor disposed in the first chamber; an air flow path extending through the second chamber, the air flow path being arranged to direct an air flow from the air inlet to the air outlet, a fan arranged in the air flow path; a coolant leak detection system configured to detect a coolant leak within the housing; and an inducer disposed in the housing, the inducer configured to move air from the first chamber into the air flow path upon detection of the coolant leak by the coolant leak detection system. Aspect 2. The air conditioning unit of aspect 1, wherein the inducer is disposed on the partition wall and above an opening extending through the partition wall. Aspect 3. The air conditioning unit according to aspect 1 or 2, wherein the inducer is an inducer fan. Aspect 4. The air conditioning unit according to any one of aspects 1-3, wherein the inducer is configured to move air through the partition in an activated mode. Aspect 5. The air conditioning unit according to any one of aspects 1-4, wherein the inducer is configured to prevent airflow through the inducer in a deactivated mode. Aspect 6. The air conditioning unit according to any one of aspects 1-5, wherein the inducer is configured to direct the air from the first chamber into the air flow path at a location in the air flow path at which the air flow path is conditioned. Aspect 7. The air conditioning unit according to any one of aspects 1-6, further comprising: an air duct extending from the inducer to the compressor for drawing air from the vicinity of the compressor through the inducer into the air duct. Aspect 8. The air conditioning unit according to any one of aspects 1-7, wherein the refrigerant leak detection system is configured to determine a concentration of refrigerant within the housing, the inducer is configured to activate in response to the concentration of refrigerant exceeding a predetermined value. Aspect 9. The air conditioning unit according to any one of aspects 1-8, wherein the first chamber and the second chamber are enclosed by the housing and the partition wall. Aspect 13. An HVAC system configured to deliver conditioned air to a conditioned space, the HVAC system comprising: a refrigerant circuit comprising a compressor, a first exchanger, a second exchanger and an expander that are fluidly connected; a housing having a first chamber containing the compressor and a second chamber containing a fan, the housing having an air inlet and an air outlet; a partition wall disposed in the housing, the partition wall separating the first chamber from the second chamber; an air flow path extending through the second chamber, the air flow path being arranged to direct an air flow from the air inlet to the air outlet; a coolant leak detection system configured to detect a coolant leak within the housing; and an inducer disposed in the housing, the inducer configured to move air from the first chamber into the air flow path upon detection of the coolant leak by the coolant leak detection system. Aspect 14. HVAC system according to aspect 13, wherein the first heat exchanger is arranged to condition the air to provide the conditioned air; and the first heat exchanger is arranged in the second chamber. Aspect 15. The HVAC system of aspect 13 or 14, wherein the inducer is an inducer fan. Aspect 16. The HVAC system of any one of aspects 13-15, wherein the second heat exchanger is disposed in the second chamber. Aspect 17. The HVAC system of any one of aspects 13-16, wherein the refrigerant leak detection system is configured to determine a concentration of refrigerant within the enclosure and activate the inducer when the concentration exceeds a predetermined value. Aspect 18. The HVAC system of any of aspects 13-17, wherein the inducer is disposed on the partition wall and above an opening extending through the partition wall.

[0083] The terminology used herein is intended to describe particular embodiments and is not limiting. The terms "a," "an," and "the" include their plural forms unless expressly stated otherwise. The terms "comprises" and / or "comprising," as used in this specification, specify the presence of the stated features, integers, steps, acts, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, acts, elements, and / or components. In one embodiment, "connected" and "connecting" may refer to "directly connected" and "directly connecting," respectively, as described herein.

[0084] With respect to the foregoing description, it is understood that changes in detail may be made, particularly with respect to the construction materials employed and the shape, size, and arrangement of parts, without departing from the scope of the present disclosure. This specification and the described embodiments are merely exemplary, and the true scope of the disclosure is set forth in the appended claims.

[0085] A system for an air conditioning unit is provided. The air conditioning unit comprises: a housing having a first chamber and a second chamber separated from the first chamber by a partition wall disposed in the housing, the housing having an air inlet and an air outlet. A refrigerant circuit has a compressor disposed in the first chamber. An air flow path extends through the second chamber. The air flow path is arranged to direct airflow from the air inlet to the air outlet, and a fan is disposed in the air flow path. A refrigerant leak detection system is configured to detect a refrigerant leak within the housing. An inducer is disposed in the housing. The inducer is configured to move air from the first chamber into the air flow path upon detection of the refrigerant leak by the refrigerant leak detection system.

Claims

[1] Air conditioning unit comprising: a housing having a first chamber and a second chamber separated from the first chamber by a partition disposed in the housing, the housing having an air inlet and an air outlet; a refrigerant circuit having a compressor disposed in the first chamber; an air flow path extending through the second chamber, the air flow path being arranged to direct an air flow from the air inlet to the air outlet, a fan arranged in the air flow path; a coolant leak detection system configured to detect a coolant leak within the housing; and an inducer disposed in the housing, the inducer configured to move air from the first chamber into the air flow path upon detection of the coolant leak by the coolant leak detection system. [2] The air conditioning unit according to claim 1, wherein the inducer is disposed on the partition wall and above an opening extending through the partition wall. [3] An air conditioning unit according to any one of claims 1-2, wherein the inducer is an inducer fan. [4] An air conditioning unit according to any one of claims 1-3, wherein the inducer is arranged to move air through the partition wall in an activated mode. [5] An air conditioning unit according to any one of claims 1-4, wherein the inducer is arranged to prevent air flow through the inducer in a deactivated mode. [6] An air conditioning unit according to any one of claims 1-5, wherein the inducer is arranged to direct the air from the first chamber into the air flow path at a location in the air flow path at which the air flow path is conditioned. [7] Air conditioning unit according to any one of claims 1-6, further comprising: an air duct extending from the inducer to the compressor for drawing air from the vicinity of the compressor through the inducer into the air duct. [8] An air conditioning unit according to any one of claims 1-7, wherein the refrigerant leak detection system is arranged to determine a concentration of refrigerant within the housing, the inducer is arranged to activate in response to the concentration of refrigerant exceeding a predetermined value. [9] An air conditioning unit according to any one of claims 1-8, wherein the first chamber and the second chamber are enclosed by the housing and the partition wall. [10] Heating, ventilation, air conditioning, and refrigeration (HVAC) system designed to deliver conditioned air to a conditioned space, the HVAC system comprising: the air conditioning unit according to any one of claims 1-9, wherein the refrigerant circuit comprises the compressor, a first heat exchanger, a second heat exchanger and an expander which are fluidly connected.

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