The gas passes through a long pipe (usually coiled into a solenoid) to let the heat escape into the surrounding air. Metals such as copper have strong thermal conductivity 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 attached to the pipes to increase the heat dissipation area to accelerate heat dissipation, and air convection is accelerated through the fan to take away heat.

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

The single-stage steam compression refrigeration system is composed of four basic components: refrigeration compressor, condenser, throttle valve and evaporator, which are connected in turn with pipes to form a closed system. The refrigerant circulates continuously in the system, changes its state, and exchanges heat with the outside.