Evaporator coils are specially made air conditioner parts that play an important role in the proper functioning of any AC unit. They condition the air in a room, and as the air passes over the coil, heat is removed and cooler air is sent back out through the air conditioner. Humidity is also taken out of the air by the coil, which works with the air conditioner condenser unit to condense the water in the air. There are three types of evaporator coils.

Evaporative coils are a key feature of air conditioners.

Vertical Evaporator Coil

Vertical evaporator coils are generally used in vertical air conditioners. Vertical air conditioners use what is called an upflow/downflow because the air in the unit flows either up or down as it passes through the coil. Vertical coils take preprocessed air and condense the heat from this air into water. After the condensation process, the coil directs the water to a drain, which thus lowers the overall humidity of the dwelling.

Cased Evaporator Coil

Cased coils are horizontally positioned and are normally covered by a metal casing. They are one of the most commonly used coils in an air conditioning system, and serve a near identical function to vertical coils, with their main difference being shape and size. Depending on the configuration of the air conditioning unit, either a vertical or cased evaporator coil may fit better for installation purposes.

Uncased Evaporator Coil

Uncased evaporator coils can be placed in either vertical or horizontal positions, and have no outer casing covering the coils. Because of this lack of covering, they are easily customizable and good for unique air conditioners that may require technicians to reconfigure the coil shape in order to fit the device.


Regardless of the type of coil you have, it is important to take good care of the coils to ensure proper functioning. Evaporator coils are made from metal and are thus subject to rust and other types of wear. Because of this, you should check your coils regularly and replace them when necessary. This will keep your AC in good working condition and your home comfortably cooled. Keeping your evaporator coil in good condition also maximizes the amount of fresh air running through your home or office space, helping to increase air flow and maintain a healthy environment.