What is the function of the evaporator coil in a heat pump?

The function of the evaporator coil in a heat pump is to absorb heat from the indoor air. In the context of heating, the evaporator coil operates by allowing the refrigerant inside it to evaporate, absorbing heat from the surrounding air in the process. This heat absorption is critical because it converts the refrigerant from a liquid state into a gaseous state, and this heat extracted is then used to warm the indoor space, providing comfort.

When air passes over the evaporator coil, it transfers its heat to the refrigerant, leading to a drop in the air temperature within the room, which is the cooling function of the heat pump during the cooling season. In heating mode, the heat absorbed is transferred and ultimately released into the home after subsequent steps in the heat pump cycle. Understanding this function is essential for comprehending how heat pumps operate and their role in climate control within residential settings.