The gas is passed through a long tube (usually coiled like a solenoid) to allow the heat to escape into the surrounding air. Metals such as copper conduct heat well and are often used to transport steam. In order to improve the efficiency of the condenser, heat sinks with excellent heat conduction performance are often added to the pipes to increase the heat dissipation area, so as to accelerate heat dissipation and speed up air convection through the fan to take the heat away.

The refrigeration principle of general refrigerator is that the compressor compresses the working medium from low temperature and low pressure gas into high temperature and high pressure gas, and then condenses into medium temperature and high pressure liquid through the condenser. After the throttle valve is throttled, it becomes the liquid of low temperature and low pressure. The low-temperature and low-pressure liquid working medium is sent to the evaporator, where it absorbs heat and evaporates into the low-temperature and low-pressure steam, which is transported to the compressor again to complete the refrigeration cycle.

Single-stage steam compression refrigeration system is composed of four basic components: refrigeration compressor, condenser, throttle valve and evaporator. They are successively connected by pipes to form a closed system. The refrigerant constantly circulates in the system, changes state and exchanges heat with the outside world.