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First Choice Heating & Cooling Blog

How Dirty Coils Affect Your Air Conditioning

ac-coilsWe’ve already written our seasonal blog to remind our customers about the importance of scheduling regular air conditioning maintenance with our technicians. But an extra reminder never hurts, and in this case we want to talk about one of the essential jobs we do during maintenance and why it’s so important—cleaning the refrigerant coils of an AC.

What are refrigerant coils?

Refrigerant coils are tubes of copper—a metal that easily conducts heat—that channel refrigerant so the refrigerant can react with the external air. The coils have fins on them to increase the surface area and allow for even easier heat exchange. 

There are two sets of coils in your air conditioning system: the indoor coil (the evaporator coil), which is located in the air handler inside your house, and the outdoor coil (the condenser coil), which is in the outdoor condensing cabinet.

When your AC runs, cold refrigerant moves through the indoor coil. The cold refrigerant evaporates as it comes into contact with warm air passed through the air handler and absorbs heat from the air, cooling it down. When the hot refrigerant moves through the outdoor coil, it condenses to release heat outside. This is how the heat exchange process in your AC works, moving warmth from inside your house and putting it outside. 

How the coils become dirty

The outdoor coils are exposed to the elements and the weather, so they can easily pick up dirt and debris. It can also pick up grass clippings and mulch, which is why we don’t recommend mowing or gardening close to the condenser cabinet. The indoor coil can pick up dust and other debris pulled into the AC through the return ducts, although keeping a clean blower filter in place will help prevent this. High humidity can also cause mold and mildew to develop over the indoor coil.

During regular maintenance, our technicians inspect the coils and clean them so they’ll be best able to handle the coming stresses of summer. 

The negative effect of dirty coils

Any layer of dirt or grime on the coils inhibits them from efficiently carrying out heat transfer. It’s a layer of insulation, and that makes it harder for the coils to either absorb or release heat. You can expect your AC to need to run longer because of dirty coils, and thus cost you more to operate. The extra wear on the system can shorten its service life and lead to extra air conditioning repair in Brighton, MI.

A dirty evaporator coil is at another risk, which is freezing over. If the coil can’t absorb enough heat to raise the temperature of the freezing refrigerant moving through it, the coil will remain too cold. The moisture along the coil will freeze, and this will lead to a chain reaction of further restricting the heat absorption properties of the coil.

Remember, your best defense against dirty coils is professional maintenance. Let our technicians give your system the inspection, tune-up, and cleaning it needs to make this summer a breeze.

First Choice Heating & Cooling serves Fenton, Linden, Holly, and the surrounding areas. If your home had a voice … it would call First Choice.

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