Evaporator Coils

An evaporator coil works with an air conditioning or heat pump system to supply warm air or cool air to a space. They work with condenser coils, liquid refrigerant, and a blower motor or fan to either add or remove heat energy in the air.

In split system air conditioners, refrigerant circulates between the indoor unit and the outdoor unit.

• As it moves, the refrigerant travels between the evaporator and condenser coils. As the refrigerant passes through the evaporator coil, the blower fan pulls hot air from the room and passes it over the coil.
• The refrigerant absorbs the heat from the air and travels to the compressor and condenser coil.
• Using pressure, the condenser coil allows the refrigerant to release the heat energy.
• This process repeats until the home reaches the set temperature.

The evaporator coil may come built inside the air handler or packaged unit, or they may come inside their own cabinet. An evaporator coil built into its own cabinet can mount near the air handler. They typically mount above or below the air handler depending on the direction of the airflow.

To help avoid a dirty evaporator coil, change the air filter regularly to keep up airflow and to keep the coil surfaces free of dirt. Maintaining airflow and refrigerant levels can help avoid a frozen evaporator coil. Contact an HVAC professional for HVAC maintenance such as maintaining the refrigerant level or cleaning the coils.

In an AC system, the evaporator coil removes heat and moisture from the indoor air while the condenser coil expels the heat outdoors.

The evaporator coil typically sits indoors and removes heat and moisture from the indoor air for cooling. The refrigerant, which absorbs the heat energy, then moves to the outdoor unit where the condenser coil releases that heat.

An A-Coil works as a type of evaporator coil. The coils form two slanted sides which connect at the top. This shape resembles the letter ‘A.’ The shape allows moisture collecting on the coil to drip into a drain pan, which then drains out of the home or building.