An air conditioning system, including a compressor, two outdoor heat exchange units, a liquid pipe used for communicating with indoor units, a high-pressure gas tube and a low-pressure gas tube; the air conditioning system further includes a valve assembly. One outdoor heat exchange unit has a first state in which one end thereof communicates with the high-pressure gas tube and another end thereof communicates with the liquid pipe, and has a second state in which one end thereof communicates with the low-pressure gas tube and the other end thereof communicates with the liquid pipe. Further disclosed is a control method for the air conditioning system.

An indoor heat exchanger in an indoor unit of an air conditioning apparatus, includes: flat tubes that are juxtaposed in a vertical direction and that each comprise a flow channel that allows refrigerant to pass through an inner portion thereof, and heat transfer fins joined to the flat tubes. The heat transfer fins each include: a first portion that extends continuously in the vertical direction; and second portions that are disposed between the flat tubes. The first portion and the second portions are continuous. 4.0DP/HT10.0 where HT is a height of each of the flat tubes and DP is a pitch of the flat tubes.

A stub pipe housing and a method for installing a stub pipe housing in a heating, ventilation, and air conditioning (HVAC) system, the stub pipe housing comprising a first end for sealed contact with an external surface of a cabinet in the HVAC system and a non-permeable material extending to a second end for sealed contact with an external pipe. Sealed contact between the first end and the cabinet, sealed contact between the second end and the external surface, and the non-permeable material ensures any fluid escaping the connection between the stub pipe and the external pipe is directed to the cabinet. The stub pipe housing supports the connection using resilient material, rigid material with compliant seals or some combination. Fluids are directed to flow through the stub pipe opening in the cabinet or directed to flow through other openings.

A stub pipe housing and a method for installing a stub pipe housing in a heating, ventilation, and air conditioning (HVAC) system, the stub pipe housing comprising a first end for sealed contact with an external surface of a cabinet in the HVAC system and a non-permeable material extending to a second end for sealed contact with an external pipe. Sealed contact between the first end and the cabinet, sealed contact between the second end and the external surface, and the non-permeable material ensures any fluid escaping the connection between the stub pipe and the external pipe is directed to the cabinet. The stub pipe housing supports the connection using resilient material, rigid material with compliant seals or some combination. Fluids are directed to flow through the stub pipe opening in the cabinet or directed to flow through other openings.

An indoor unit includes: a blow-out port through which air is blown into a space to be air-conditioned; a refrigerant flow path through which flammable refrigerant gas flows; and a refrigerant detection sensor that detects the flammable refrigerant gas that leaks out of the refrigerant flow path. The refrigerant detection sensor faces the space. The refrigerant detection sensor includes a casing. The casing includes a gas intake port that takes in the flammable refrigerant gas. An outside-air-flow-area part of the refrigerant detection sensor is disposed outside of an air flow area through which the air blown through the blow-out port passes. The gas intake port is disposed on the outside-air-flow-area part.

An indoor unit includes: a blow-out port through which air is blown into a space to be air-conditioned; a refrigerant flow path through which flammable refrigerant gas flows; and a refrigerant detection sensor that detects the flammable refrigerant gas that leaks out of the refrigerant flow path. The refrigerant detection sensor faces the space. The refrigerant detection sensor includes a casing. The casing includes a gas intake port that takes in the flammable refrigerant gas. An outside-air-flow-area part of the refrigerant detection sensor is disposed outside of an air flow area through which the air blown through the blow-out port passes. The gas intake port is disposed on the outside-air-flow-area part.

An air conditioning apparatus 1 includes a compressor (321), an indoor heat exchanger (242) that is a use-side heat exchanger that exchanges heat with first air (F1), an outdoor heat exchanger (323) that is a heat-source-side heat exchanger that exchanges heat with second air, a refrigerant, a first duct (209), and a casing (230). The refrigerant contains at least 1,2-difluoroethylene, and circulates in the compressor (321), the indoor heat exchanger (242), and the outdoor heat exchanger (323) to repeat a refrigeration cycle. The first duct (209) supplies the first air (F1) to a plurality of rooms in an interior. The casing (230) includes a use-side space (SP2) that is connected to the first duct (209) and that accommodates the indoor heat exchanger (242). The casing (230) is configured to allow the first air (F1) after heat exchange with the refrigerant at the indoor heat exchanger (242) to be sent out to the first duct (209).

An air conditioning apparatus 1 includes a compressor (321), an indoor heat exchanger (242) that is a use-side heat exchanger that exchanges heat with first air (F1), an outdoor heat exchanger (323) that is a heat-source-side heat exchanger that exchanges heat with second air, a refrigerant, a first duct (209), and a casing (230). The refrigerant contains at least 1,2-difluoroethylene, and circulates in the compressor (321), the indoor heat exchanger (242), and the outdoor heat exchanger (323) to repeat a refrigeration cycle. The first duct (209) supplies the first air (F1) to a plurality of rooms in an interior. The casing (230) includes a use-side space (SP2) that is connected to the first duct (209) and that accommodates the indoor heat exchanger (242). The casing (230) is configured to allow the first air (F1) after heat exchange with the refrigerant at the indoor heat exchanger (242) to be sent out to the first duct (209).

An HVAC system is disclosed. The HVAC system includes at least one heat exchanger unit disposed within a predefined area. The HVAC system further includes at least one frame cooperating with each of the at least one heat exchanger unit. The at least one frame includes a guiding assembly configured to move each of the at least one heat exchanger unit across the predefined area. The guiding assembly includes a guiding rail. The guiding assembly further includes at least one slider cooperating with the guiding rail to enable movement of the at least one heat exchanger unit. Each of the at least one slider comprises a fastening unit configured to attach a heat exchanger unit to an associated slider. The guiding assembly includes at least one actuator, wherein each of the at least one actuator is configured to move an associated slider from the at least one slider.

An HVAC system is disclosed. The HVAC system includes at least one heat exchanger unit disposed within a predefined area. The HVAC system further includes at least one frame cooperating with each of the at least one heat exchanger unit. The at least one frame includes a guiding assembly configured to move each of the at least one heat exchanger unit across the predefined area. The guiding assembly includes a guiding rail. The guiding assembly further includes at least one slider cooperating with the guiding rail to enable movement of the at least one heat exchanger unit. Each of the at least one slider comprises a fastening unit configured to attach a heat exchanger unit to an associated slider. The guiding assembly includes at least one actuator, wherein each of the at least one actuator is configured to move an associated slider from the at least one slider.