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Your AC’s Evaporator Coils—Explained!

air-conditioning-coilsIf you’ve heard an HVAC technician discussing making repairs to an air conditioner—possibly your air conditioner—you may have overheard terms you didn’t fully understand. For example, the evaporator coils. You might know evaporate coils have something to do with cooling the house, but not exactly what.

We’re here to help you better understand this essential part of how your air conditioner works. This isn’t to give you DIY advice, however! When it comes to fixing trouble with the evaporator coils, or any other part of your AC, always trust professionals for the service.

Evaporator Coils Absorb Heat From Your Home

This is the basic job of the coils: draw thermal energy from air inside your home. When the coil removes this thermal energy (our cute name for heat), it cools down the air. Remember, cooling isn’t a form of energy, it’s the absence of a form of energy: heat! The evaporator coils cool the air around them, and when the blower fan moves air across the coils, it carries the cooled air from the coils into the rest of the house. Presto! A pleasantly cool house on a hot day.

How the Evaporator Coils Do Their Job

Let’s dig deeper into the “how” …

Evaporator coils are usually made from aluminum, a light metal allowing for the easy transfer of heat from outside the coils to inside. If you look inside the indoor cabinet of your AC, the coils are the parts that look like a series of pipes weaving back and forth.

The chemical refrigerant circulating through the air conditioner passes over these metal pipes. At this point (assuming the air conditioner is operating correctly and in cooling mode) the refrigerant moving through the coils is extremely cold because it released heat through the outdoor condenser coils and was then depressurized. The warmer air running over the coils from the blower fan causes the refrigerant to evaporate. When a liquid evaporates, it draws heat into it. The air around the coils becomes cool, while the refrigerant in the coils warms up. The refrigerant returns to the compressor outdoors where it is pressurized and heated up to start the process of heat exchange all over again.

Evaporator Coil Troubles

To do their job efficiently, evaporator coils must remain clean. Grime or corrosion will make it harder for the coils to absorb heat. This not only means air that isn’t as cool as expected, it can also cause the refrigerant in the coil to stay so cold that ice starts to develop along it. If you ever seen ice on the evaporator coil, something is wrong! You may need to arrange for air conditioning repair in Howell, MI to have the coils cleaned. If the coils have corroded, the best step is to have them replaced.

Please don’t attempt to clean the coils yourself or scrape ice off them. You may end up damaging the coils and worsening the problem. Let HVAC experts see any coil problems are resolved accurately.

Schedule the HVAC repairs you need with First Choice Heating & Cooling. If Your Home Had a Voice, It Would Call First Choice!

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