Homeowner Handbook: What kind of coils does my HVAC system use?

At MTB, we’re the HVAC experts. Our job is to not only fix and keep your HVAC system running at full capacity, but to also educate you on your system so you can make informed decisions.

So, what kind of coils does your HVAC system use?

There are two kinds: evaporator coils and condenser coils. While they perform similar functions, they work under very different conditions.

You’re probably envisioning what these coils look like. They aren’t a metal spiral like the ones you see in an old-fashioned mattress. They are flat panels that house a copper tube that bends back and forth.

To keep you cool, your HVAC system pumps refrigerant that can easily change between a liquid and gas state. 

Your system’s evaporator coil is housed in your indoor unit. It’s responsible for the cool air in your home. How? The cold refrigerant travels through your evaporator coil, then air from the intake vent is blown across the coil and back into your home via your duct system. 

The condenser coil is responsible for expelling the heat. Remember how we said your refrigerant can easily transform from a liquid to a gas? This is where it happens. After the refrigerant has traveled through the evaporator coil, it goes through a compressor where it transforms into a hot, high-pressure gas. Then, the gas goes through the outdoor condenser coil and is cooled down by a giant fan. As the heat is removed, it comes out the top of your outdoor unit.

After the air has left your condenser coil, it’s cooler but still has pressure, so it goes to an expansion chamber where the pressure dissipates. This is where it comes full circle — the refrigerant rapidly cools down and then flows back to the evaporator coil.

Why is this important to me?
It’s imperative that you keep your evaporator and condenser coils clean. Dust and dirt can inhibit your coils from working properly, and in turn, limit the heat transfer process and efficiency of your HVAC system. During your preventive maintenance checkup, an MTB technician will clean your coils. Schedule your appointment today.