What is the working principle of parking air conditioning?

The working principle of parking air conditioning is as follows:
Parking air conditioning is an air conditioning system that is driven by a battery or other device when the vehicle is parked and the engine is turned off. Its working principle is to use refrigerant to circulate inside the air conditioning system. The refrigerant is transformed from a liquid state to a gaseous state in the evaporator, absorbing heat inside the cab and reducing the temperature inside the cab. After being compressed by the compressor, the gaseous refrigerant enters the condenser again. After being cooled by the high-temperature and high-pressure gaseous heat dissipation, it is converted into a liquid and carries the heat out of the driver's cabin to the external environment.
This process is constantly circulating, achieving stable control of the temperature inside the cab by controlling the circulation and temperature of the refrigerant. In addition, the parking air conditioning also has a ventilation device, which introduces fresh external air into the driver's cab and expels polluted air inside the cab to maintain fresh and clean air.
It is worth noting that the compressor of the parking air conditioning is usually powered by the vehicle battery, so there must be a battery voltage protection function during the operation of the parking air conditioning. If the parking air conditioning is used for a long time, it may cause over discharge of the vehicle battery, so it is necessary to control the usage time reasonably.
Overall, the working principle of parking air conditioning is to utilize the circulation of refrigerant within the air conditioning system and the role of key components such as compressors, condensers, and evaporators to achieve cooling and temperature control of the air inside the driver's cabin. At the same time, there are ventilation devices to keep the air fresh and clean. When using parking air conditioning, it is necessary to control the usage time reasonably to avoid over discharging the vehicle battery.