The condenser and evaporator are heat exchange containers for automotive air conditioning systems. The high-pressure and high-temperature refrigerant gas in the condenser transfers heat to the outside world (releases heat) and condenses (liquefies) into a high-pressure liquid, thereby changing the form of the refrigerant, but the pressure remains basically unchanged; Low pressure liquid undergoes heat exchange (absorption of heat) with the outside environment (cab) in the evaporator, resulting in boiling (vaporization) phenomenon, which continuously lowers the temperature of the space. After boiling (vaporization), low-pressure refrigerant gas is produced, thereby changing the form of the refrigerant, but the pressure remains basically unchanged.

The most common faults in condensers and evaporators are blockage and leakage of dirt. Dirt blockage can be repeatedly blown with nitrogen or compressed air that has been dried until it is clean and unobstructed.

The condenser and evaporator must be regularly cleaned of dirt on the surface, and attention should be paid not to overturn or damage the heat transfer fins to ensure their heat transfer performance.

The leakage of the condenser can generally be seen from the surface, such as scratches, scratches, or oil stains leaking from the leakage point. The leakage of the evaporator is usually difficult to detect due to low pressure and condensation on the outer surface, which is hidden inside the evaporator box.

The leakage detection of condensers and evaporators is generally achieved through airtightness tests (pressure tests), with a test pressure of 2.0-2.4 MPa for condensers; Evaporator 1.2MPa.

Under normal circumstances, the surface temperature of the evaporator is very low, but only a large amount of condensation occurs and cannot frost or freeze.