An air conditioner 1 includes: an outdoor heat exchanger 14; an outdoor fan 12 for blowing air to the outdoor heat exchanger; an outdoor fan motor 20 that drives the outdoor fan; an outdoor fan inverter 21 that drives the outdoor fan motor; and a control unit 31 that generates a rotation-speed command voltage for controlling the rotation number of the outdoor fan motor. In addition, the control unit starts a defrost operation of the outdoor heat exchanger, based on the rotation-speed command voltage. In this manner, it is possible to achieve an outdoor device of an air conditioner in which there is no need to provide a current detecting sensor, and it is possible to detect frost formation over the heat exchanger during a heating operation and to perform a defrost operation at low costs.

A heat source unit and a refrigeration cycle apparatus that are able to reduce damage to a connection pipe when a refrigerant containing at least 1,2-difluoroethylene is used are provided. An outdoor unit (20) that is connected via a liquid-side connection pipe (6) and a gas-side connection pipe (5) to an indoor unit (30) including an indoor heat exchanger (31) and that is a component of an air conditioner (1) includes a compressor (21) and an outdoor heat exchanger (23). A refrigerant containing at least 1,2-difluoroethylene is used as a refrigerant. A design pressure of the outdoor unit (20) is lower than 1.5 times a design pressure of each of the liquid-side connection pipe (6) and the gas-side connection pipe (5).

In one embodiment, an apparatus includes an insert for an evaporator coil. The insert is located within the evaporator coil. The insert for the evaporator coil reduces refrigerant charge in the evaporator coil and causes refrigerant flowing through the evaporator coil to change direction. The insert for the evaporator coil includes a solid core and a plurality of support legs.

Embodiments of the present disclosure generally relate to heat transferring apparatuses and methods. The apparatus and methods utilize the Joule-Thomson effect to remove heat from a heat source to facilitate cooling of the heat source. In one example, an apparatus receives heat from an object to be cooled. The received heat is used to pressurize a fluid. The pressurized fluid is depressurized through a venturi using vapor pressure as a driving force, thus cooling the fluid.

A cooling system is designed to operate in two different modes. Generally, in the first mode, when parallel compression is needed, certain valves are controlled to direct gaseous refrigerant from a tank to a compressor in the system and to direct refrigerant from low side heat exchangers towards other compressors. In this manner, a compressor in the system is transitioned to be generally a parallel compressor. In the second mode, when parallel compression is not needed, the valves are controlled to return the refrigerant flow back to normal.

An air conditioning unit capable of performing a refrigeration cycle using a small-GWP refrigerant is provided. A refrigeration cycle apparatus (1, 1a to 1m) includes a refrigerant circuit (10) including a compressor (21), a condenser (23, 31, 36), a decompressing section (24, 44, 45, 33, 38), and an evaporator (31, 36, 23), and a refrigerant containing at least 1,2-difluoroethylene enclosed in the refrigerant circuit (10).

A cooling device 10 comprising a first evaporation unit 11, a second evaporation unit 12, a first condensation unit 21, a second condensation unit 22, common piping CP, a compressor 30, an expansion valve 40, a first valve 71, and a second valve 72. The common piping CP combines liquid-phase refrigerant LP-COO flowing from the first condensation unit 21 and liquid-phase refrigerant LP-COO flowing from the second condensation unit 22. The first valve 71 adjusts the liquid-phase refrigerant amount LP-COO flowing into the first evaporation unit 11. The second valve 72 adjusts the liquid-phase refrigerant amount LP-COO flowing into the second evaporation unit 12. In addition, the pressure P0 inside the common pipe CP is greater than the respective pressures P1 and P2 inside the first evaporation unit 11 and the second evaporation unit 12. Thus, the length of the piping can be shortened.

There is provided a refrigeration cycle apparatus in which good lubricity can be achieved when a refrigeration cycle is performed using a refrigerant having a sufficiently low GWP. The refrigeration cycle apparatus contains a refrigerating oil and a refrigerant composition containing a refrigerant containing trans-1,2-difluoroethylene (HFO-1132(E)), trifluoroethylene (HFO-1123), and 2,3,3,3-tetrafluoro-1-propene (R1234yf).

High power of a compressor that compresses a mixed refrigerant containing at least 1,2-difluoroethylene is achieved. A compressor (100) employs an induction motor (70) as a motor that drives a compression unit (60) that compresses a mixed refrigerant containing at least 1,2-difluoroethylene, and thus, high power is enabled at comparatively low costs.

High efficiency of a compressor that compresses a mixed refrigerant containing at least 1,2-difluoroethylene is achieved. A compressor (100) includes a motor (70) that has a rotor (71) including permanent magnets (712) and thus is suitable for a variable capacity compressor in which the number of rotations of the motor can be changed. In this case, it is possible to change the number of rotations of the motor in accordance with an air conditioning load in an air conditioner (1) that uses a mixed refrigerant containing at least 1,2-difluoroechylene. It is thus possible to enable high efficiency of the compressor (100).