How does a heat pump work?

1. Evaporation: The process begins with the evaporator, which is located in the area where heat needs to be absorbed (e.g., indoors for heating or outdoors for cooling). A refrigerant, typically a fluid with low boiling point, circulates through the evaporator coil. As the refrigerant absorbs heat from the surrounding air, water, or ground, it evaporates into a low-pressure gas.

2. Compression: The gaseous refrigerant is then compressed by the compressor. The compression increases both its pressure and temperature. As a result, the refrigerant transforms into a high-pressure and high-temperature gas.

3. Condensation: The high-pressure gas enters the condenser coil, which is located in the area where the heat is to be released (e.g., outdoors for heating or indoors for cooling). The refrigerant condenses into a liquid state as it releases heat to the outside environment. This heat transfer causes the refrigerant to cool down.

4. Expansion: The condensed liquid refrigerant passes through the expansion valve, where its pressure is reduced. This pressure drop causes the refrigerant to evaporate and return to a low-pressure gas state. The refrigerant then flows back to the evaporator to repeat the cycle.

During the cycle, a reversing valve can be used to switch the direction of heat transfer. In heating mode, the evaporator is located outdoors to absorb heat from the outside environment and release it indoors. In cooling mode, the evaporator is located indoors to absorb heat from the indoor air and release it outdoors.