A turbo compressor that has a pressure equalizing tube that circulates a gas from a gear unit accommodation space toward an IGV accommodation space, and an oil separation device that is provided in the gear unit accommodation space to separate lubricating oil that is contained in the gas, in which the oil separating device has a suction duct that communicates with the pressure equalizing tube, and the suction duct has a centrifugal separation portion provided with a first demister, a second demister provided on the downstream side of the first demister in relation to the suction direction, and a curved passage provided between the first demister and the second demister.

A refrigerant loop of a vapor injection heat pump includes a compressor, first and second expansion valves, and first and second separator valves. The separator valves allow an entire refrigerant flow to pass therethrough or operate to separate vapor and liquid components of expanded refrigerant and inject the vapor component into a suction port of the compressor. Vapor injection occurs in both heating and cooling modes of operation and may depend upon an ambient condition (e.g., high or low ambient temperatures). An accumulator receives an output refrigerant of the heat exchangers dependent upon the mode and directs a vapor component into another suction port of the compressor. A control module controls at least the first and second expansion valves and first and second separator valves dependent upon the mode of operation which include, among others, heating, cooling, and dehumidification and re-heating.

A heat pump water heater has a tank, a burner in communication with a fuel source, a flue, and a heat pump system. The heat pump system has a refrigerant path, at least a portion of which forms an evaporator in thermal communication with the flue. Another portion of the refrigerant path is in thermal communication with the water tank volume so that heat transfers from the refrigerant to the water tank volume.

A hydronic system is provided that includes a primary fluid loop that includes a thermal source for heating or cooling working fluid, dual secondary fluid loops that include respective thermal loads, and a decoupler. One leg of a supply tee at an output of the source places the output in fluid communication with one end of a decoupler and, beyond the decoupler, with the input of a thermal load of a first secondary fluid loop. Another leg of the supply tee places the source output in fluid communication with the input of a thermal load in a second secondary fluid loop. One leg of a return tee at an input of the source places the input in fluid communication with the other end of the decoupler and, beyond the decoupler, with the output of the thermal load of the first secondary fluid loop. Another leg of the return tee places the input of the source in fluid communication with the input of the thermal load in the second secondary fluid loop.

Provided is an air conditioner system for a vehicle. The air conditioner system for a vehicle includes a compressor, an integral condenser in which a water cooling region and an air cooling region are formed integrally with each other, an expansion valve, and an evaporator, wherein the water cooling region and the air cooling region of the integral condenser are formed on one plate, such that existing air cooling and water cooling condensers may be formed integrally with each other through one-time brazing coupling, thereby reducing a package and simplifying assembling and manufacturing processes.

The present invention relates to an air conditioner system, in which an air-cooled condenser mounted on a refrigerant circulation line between a water-cooled condenser and an expansion valve and a blower fan for blowing air to the air-cooled condenser are arranged at one side of the water-cooled condenser in a state of being disposed in a row in the air flow direction and are arranged within the width of the one side of the water-cooled condenser, thereby enabling the enhancement of installability and assemblability inside an engine room by simplifying and reducing the package, reducing noise of the blower fan and securing adequate cooling performance because of the blower fan disposed between two air-cooled heat exchangers even when inflowing air is insufficient, such as in an idling condition.

Embodiments as disclosed herein are directed to a heat pump that employs at least two different refrigerants, each of which is optimized for either a cooling operation mode or a heating operation mode. The embodiments as disclosed herein can help increase the capacity and/or efficiency of a heat pump in both the cooling operation mode and the heating operation mode. In addition, the embodiments as disclosed herein may also eliminate the need for a ground source in a relatively low ambient temperature environment.

A plate heat exchanger can reduce thermal contact between a second fluid (water and a third fluid (low-temperature, low-pressure two-phase refrigerant) to enhance thermal efficiency. A plate heat exchanger (1b) includes a heat transfer plate group (102a) that performs heat exchange between a first fluid of high-temperature, high-pressure gas refrigerant and a second fluid of a heating target fluid; and a heat transfer plate group (102b) that performs heat exchange between a first fluid of low-temperature, high-pressure liquid refrigerant and a third fluid of low-temperature, low-pressure two-phase liquid refrigerant. The heat transfer plate group (102a) forms refrigerant channels including a stack of plates, has a configuration that a flow of the first fluid of high-temperature, high-pressure gas refrigerant and a flow of the second fluid are alternately aligned in the refrigerant channels, and causes the second fluid to flow in the outermost refrigerant channel.

Methods and systems for controlling a chiller system to achieve control stability while maintaining optimum efficiency. Particularly, methods and systems for controlling a centrifugal compressor speed and an inlet guide vane position that establishes three distinct regions in the control path: (i) during initial unloading from full load, the inlet guide vane position is kept at a fully open position while the centrifugal compressor speed is changed to achieve the desired cooling capacity; (ii) between an inflection point and a transition point, keeping the centrifugal compressor speed constant while the inlet guide vane position is changed to achieve the desired cooling capacity; and (iii) between the transition point and zero cooling capacity, changing both the inlet guide vane position and the centrifugal compressor speed to achieve the desired cooling capacity.

A defrost system includes: a cooling device in a freezer, and includes a casing, a heat exchanger pipe with a difference in elevation in the casing, and a drain receiver unit below the heat exchanger pipe; a refrigerating device to cool and liquefy CO.sub.2 refrigerant; and a refrigerant circuit for permitting the cooled and liquefied CO.sub.2 refrigerant to circulate to the heat exchanger pipe. The defrost system includes a bypass pipe of the heat exchanger pipe to form a CO.sub.2 circulation path; an on-off valve in the heat exchanger pipe to be closed during defrosting so that the CO.sub.2 circulation path is a closed circuit; a pressure adjusting unit for adjusting pressure of the CO.sub.2 refrigerant during defrosting; and a brine circuit as a first heating medium, in which the defrost system permits the CO.sub.2 refrigerant to naturally circulate in the closed circuit during defrosting by a thermosiphon effect.