A ducted separator in a compressor-based cooling assembly is connected to an oil/gas outlet of the compressor. The ducted separator is a pipe with at least one bend in it which collects oil in a manner which can achieve 98% oil carry over efficiency. The ducted separator may optionally be connected to a second phase separator such as a centrifugal cylinder. In that case, the height of the centrifugal cylinder can be significantly reduced compared with conventional arrangements. Alternatively, a simpler impingement surface such as one or more baffles may be used as the second phase separator or just a collection chamber.

A heat pump apparatus includes a heat source-side refrigeration cycle sequentially connecting a compressor, a heat source-side heat exchanger, an expansion valve, and a heat source side of a cascade heat exchanger, and configured to circulate refrigerant, and a load-side refrigeration cycle sequentially connecting a heat medium sending unit, a load-side heat exchanger, and a load side of the cascade heat exchanger, and configured to circulate a heat medium. The heat source-side heat exchanger and the cascade heat exchanger each have a hydraulic diameter of less than 1 mm, which is calculated by 4S/L, where S represents a cross-sectional area of a fluid passage and L represents a length of a wetted perimeter.

A refrigeration cycle (1) comprises in the direction of flow of a circulating refrigerant: a compressor unit (2); an oil separation device (4) which is configured for separating oil from an refrigerant-oil-mixture leaving the compressor unit (2); at least one gas cooler/condenser (6); and at least one evaporator (10) having an expansion device (8) connected upstream thereof. The oil separation device (4, 5) comprises: a refrigerant inlet line connected to the compressor unit (2), the refrigerant inlet line having at least a first portion (12) with a first diameter (d1); a refrigerant conduit arranged downstream of and connected to the refrigerant inlet line, the refrigerant conduit having at least a second portion (14) with a second diameter (d2), which is larger than the first diameter (d1); a refrigerant outlet line arranged downstream of and connected to the refrigerant conduit, the refrigerant outlet line having at least a third portion (16) with a third diameter (d3), which is smaller than the second diameter (d2); and an oil suction line (20) having an inlet portion (22) which opens into the second portion (14) and is configured for sucking oil from the second portion (16). The third portion (16) having the third diameter (d2) extends into the second portion (14) forming an oil separation pocket (18) between the outer diameter of the third portion (16) and the inner diameter of the second portion (14).

There are provided a heat exchange apparatus and an air conditioner in which an occurrence of uneven refrigerant distribution of a heat exchanger is reduced such that heat exchange performance improves. The heat exchange apparatus includes: a heat-transfer pipe through which a refrigerant flows; a heat exchanger in which a plurality of the heat-transfer pipes are connected to one another; a distributor that distributes the refrigerant to the plurality of heat-transfer pipes; an inflow pipe that causes the refrigerant to flow into the distributor; and a confluent pipe which is connected to an intermediate position of the inflow pipe and in which the refrigerant flowing through an inside thereof is to merge with the refrigerant flowing through an inside of the inflow pipe. A merging part between the inflow pipe and the confluent pipe is positioned in the vicinity of the distributor.

A heating, ventilation and air conditioning (HVAC) system includes a condenser (18) flowing a flow of refrigerant therethrough and to an output pipe (56) and a falling film evaporator (12) in flow communication with the condenser and having an evaporator input pipe (58) located vertically higher than the output pipe. A plurality of riser pipes (60) connect the output pipe to the evaporator input pipe. The flow of refrigerant flows through selected riser pipes of the plurality of riser pipes as required by a load on the HVAC system.

A thermoelectric heat pump air conditioner comprising an indoor air conditioner and an outdoor air conditioner. The indoor air conditioner comprises a first phase-change suppressing heat transfer plate, a thermoelectric cooling assembly and a heat exchanger. A first cooling medium pipe and a first thermally superconducting pipe are formed in the first phase-change suppressing heat transfer plate. The first thermal superconducting pipe is filled with a first heat transfer working medium. The heat exchanger is attached on a surface, away from the phase-change suppressing heat transfer plate, of the thermoelectric cooling assembly. A second cooling medium pipe is formed in the heat exchanger. The outdoor air conditioner comprises a second phase-change suppressing heat transfer plate. A third cooling medium pipe and a second thermally superconducting pipe are formed in the second phase-change suppressing heat transfer plate. The second thermally superconducting pipe is filled with a second heat transfer working medium.

An air conditioner includes an outdoor heat exchanger configured to exchange heat between a refrigerant and outdoor air; an indoor heat exchanger configured to exchange heat between the refrigerant and indoor air; a first pipe configured to provide a channel for the refrigerant flowing out of the outdoor heat exchanger and having a first inner diameter; a second pipe configured to provide a channel for the refrigerant flowing into the indoor heat exchanger; a coupling member configured to couple end portions of the first pipe and the second pipe; and a first insertion pipe inserted in the second pipe at the end portion of the second pipe and having a second inner diameter smaller than the first inner diameter of the first pipe.

An collective device for switching refrigerant flow arranged between an indoor device and an outdoor device is provided; which includes multiple high-pressure valves; multiple low-pressure valves; a high-pressure header; a low-pressure header; a high-pressure gas pipe connecting each high-pressure valve and the high-pressure header; and a low-pressure gas pipe connecting each low-pressure valve and the low-pressure header, wherein the multiple high-pressure valves are arranged next to each other in a first direction perpendicular to a vertical direction, the multiple low-pressure valves are arranged next to each other in the first direction, and the low-pressure valves, the low-pressure header, and the low-pressure gas pipe are arranged on one side in a second direction perpendicular to the vertical direction and the first direction with respect to the high-pressure valves, the high-pressure header, and the high-pressure gas pipe.

A drain valve (10) is described comprising a housing (11), a fluid inlet (12), a gas outlet (13) and at least one liquid outlet orifice (19) arranged in a liquid outlet member (20) of the housing (11). The drain valve (10) furthermore comprises a float (16) connected to a lever (17) on a first end (18). The float (16) is arranged in a float chamber (15) of the housing (11). The float chamber (15) is connected to the fluid inlet (12), the gas outlet (13) and the at least one liquid outlet orifice (19). The liquid outlet orifice (19) may be opened or closed by a closing member (21) that is connected to a second end (22) of the lever (17) and is rotatably connected to the liquid outlet member (20). If a liquid is arranged in the float chamber (15) a rise in the liquid level will result in a lift of the float (16) whereby the closing member (21) is rotated to a more open position of the at least one liquid outlet orifice (19) and vice versa. Such a drain valve should be operated at higher fluid pressures without increasing the size of the valve. To this end the liquid outlet member (20) comprises a cylinder-like section and the closing member (21) is arranged concentrically around the cylinder-like section, wherein the closing member (21) comprises a closing element (24), wherein in the open valve position of the closing member (21) the closing element (24) converges towards the closest liquid outlet orifice (19) that the closing element (24) is matched to such that the surface of the closing element (24) perpendicular to the liquid flow direction through the liquid outlet orifice (19) is minimized, and the end of the liquid outlet orifice (19) that is first exposed when the liquid outlet orifice (19) is opened has the smallest width perpendicular to the opening direction of the closing element (24).

The present disclosure provides a refrigeration system comprising a receiver for use in applications where environmentally-friendly, typically flammable refrigerants are used. The receiver is sized so that it allows for the maximum amount of refrigerant to be used when regulatory concerns restrict the total amount. The present disclosure also provides a method for selecting the size of the receiver.