Whether it is evaporation or condensation when air conditioning is heating depends on the pressure conditions. The refrigeration cycle means that when the gas refrigerant is compressed, the pressure becomes higher and it can absorb heat in a high-temperature environment, so it will condense and release heat in the condenser.
The liquid refrigerant becomes active after the expansion valve and evaporates in the evaporator to absorb heat in a relatively low temperature environment.
Heat pump cycle the same reason.
The process of refrigerant change in the condenser can theoretically be seen as an isothermal process. In fact it has three effects:
First, the air takes away the overheated part of the high-temperature air-conditioning refrigerant gas sent by the compressor, making it a dry saturated vapor;
Second, liquefaction is performed at a constant saturation temperature;
Third, when the air temperature is lower than the condensing temperature, the liquefied refrigerant is further cooled to the same temperature as the surrounding air and plays a cooling role.
The condenser is the high pressure equipment of the system when the outdoor heat exchanger is cooling (cold and warm heat pump type is the low pressure equipment in the heating state), and is installed between the compressor outlet and the throttling device.
The high-temperature and high-pressure gas (Freon) discharged from the air-conditioning compressor enters the condenser and is cooled and cooled by copper tubes and aluminum foil.
Axial flow cooling fans are installed in air conditioners, which are air-cooled, so that the refrigerant in the cooling and condensation process, the pressure is constant, the temperature decreases, from gas to liquid.