Evaporator
An evaporator is a heat exchanger in which refrigerant absorbs heat from a surrounding fluid or space and changes from liquid to vapor.
Refrigerant: A working fluid that transfers heat by changing pressure, temperature, or phase in a refrigeration system. It absorbs heat in the evaporator and leaves primarily as vapor.
Vapor-compression refrigeration: A refrigeration cycle that moves heat using a circulating refrigerant, compressor, condenser, expansion device, and evaporator. The evaporator is the cycle component that collects heat from the cooled space or fluid.
Air conditioning: The control of indoor air temperature, humidity, cleanliness, and circulation for comfort or process needs. An indoor coil evaporator removes heat from air in many air-conditioning systems.
Boiler: A vessel or heat exchanger that transfers heat to water or another fluid to produce hot fluid or vapor. Both can boil a fluid, but a refrigeration evaporator absorbs heat as part of a cooling cycle.
Latent heat: Energy absorbed or released during a phase change without changing a substance's temperature. Most heat uptake in the evaporator accompanies liquid refrigerant becoming vapor.
Expansion valve: A metering device that lowers refrigerant pressure and regulates its flow into an evaporator. It supplies the evaporator with low-pressure refrigerant according to cooling demand.
Refrigerator: An insulated appliance that keeps food and other contents cool using a refrigeration system. Its evaporator absorbs heat from the refrigerated compartment.
Heat pump: A system that transfers heat between locations by circulating a working fluid through a thermodynamic cycle. An evaporator is one component, not the complete heat-transfer system.
Boiling: The formation of vapor bubbles throughout a liquid when its vapor pressure reaches the surrounding pressure. Refrigerant boils as it absorbs heat at the evaporator's operating pressure.
Compressor: A machine that raises a gas's pressure by reducing its volume or adding mechanical energy. It draws vapor from the evaporator outlet and drives refrigerant circulation.