Get up to $2000 tax credit on select AC systems! Call now to learn more.

Get up to $2000 tax credit on select AC systems! Call now to learn more.

Get up to $2000 tax credit on select AC systems! Call now to learn more.

Dirty Evaporator Coils Are Killing Your AC!


Dirt is the arch enemy of your air conditioner. A dirty evaporator coil can spell real trouble for your whole system. Your AC is one of the most important, valuable systems in your home and it’s important to have your coils checked on a regular basis to help it run efficiently and stay healthy for the long haul.

How Do I Know if I Have a Dirty Evaporator Coil?

You may not know this, but your air conditioner “talks” to you. Just like other kinds of machines and complicated systems, it will start giving you tell-tale signs when there is something wrong. Since the evaporator coils absorb the heat in your home as the air is drawn through the return ducts by a blower fan, it is a prime source for buildup. That sets the stage for trouble.

Most Common Problems Caused by Dirty Evaporator Coils

1. Inadequate Cooling

Have you noticed a difference in the temperature of the air coming out of the vents? If you have buildup on the coils, the air conditioner will often still come on, but it won’t do a good job. The dirt serves as a barrier to the air and the metal coils can’t take in enough of the heat circulating inside the house and through the air vents. The efficiency of the cooling process can be substantially compromised.

2. AC is Constantly Running

The thermostat in your home monitors the temperature and tells your air conditioner when to turn on. Should be simple, right? But since it is made to run in cycles, it can be a real problem if you have a dirty evaporator coil. It just keeps running and running, trying to do its job — and wearing itself out. The dirtier the coil gets, the longer the cycles will extend. If this goes on too long, it can shorten the life of the whole system.

3. The Coil Can FREEZE!

Freezing is one of the worst things that can happen to the coil in your air conditioner. Do you know what happens when the AC coil freezes? Since the dirt buildup restricts the amount of heat it can absorb, condensation can accumulate on the coil. This water then turns to ice. When this happens, your air conditioner can break down — causing unnecessary, unexpected expenses, and even stress to you and your family.

Paying attention to how your air conditioner is running will help you to know if you need AC maintenance on your system.

Where is the Evaporator Coil Located in an Air Conditioner?

When people think about the parts of an air conditioning system, they usually visualize the large unit on the outside, the vents, or even the thermostat. As a critical component in the cooling function of your system, the evaporator coil is located on the inside of the internal unit or near the air handler where the blower fan is located. It is typically made of steel, aluminum or copper because these are the metals that do the best job in conducting heat.

Since it is located on the inside of the unit, it is important to contact a professional to clean a dirty evaporator coil. HVAC professionals have the expertise and the tools to the job correctly, efficiently, and safely.

What Can I Do to Prevent a Dirty Evaporator Coil?

It is not a homeowner’s job to know how to check an evaporator coil, but there are things that you can do to help prevent the buildup and subsequent problems associated with it getting dirty. You have the power!

1. Change Your Air Filters on a Regular Basis

This is one of the easiest (and most effective) things a homeowner can do to keep your AC running well and help it to have a nice, long life. Every 60-90 days is pretty standard, but if you have pets that shed a lot or anyone in the home that has respiratory allergies or other breathing issues, change them every 30 days. And while you’re at it — take out your vacuum cleaner and clear out accumulated dust, pet hair or other debris in and around the vents.

2. Upgrade the Type of Air Filters You Use

A high-quality air filter will take out more particles from the indoor air circulating through your vents. An important note here: know how high you can go. If you get a filter that exceeds the rating that your particular unit can handle, it can wear out your air conditioner faster. You can typically find this information in the unit’s manual, or consult with a professional when getting your regular maintenance performed.

3. Schedule a Maintenance Call Twice Per Year

Your air conditioning system should be regularly maintained for optimum health. Qualified HVAC technicians go through a 16 point checklist, making sure there are no leaks, spot small problems before they turn big, and keeping everything running smoothly and efficiently. With the constant vibration of a running air conditioner, parts can get out of alignment and need to be checked and adjusted as needed. Regular maintenance will also save you money — spending a little to keep your AC in good shape is much better than having to drop down a big, unexpected payment when it breaks down. Regular maintenance will also save you money on your utility bills!

Don’t let a dirty evaporator coil kill your AC. Do your part and change the air filters on a regular basis and then make sure to keep up with regular maintenance. Preventative measures like this will go a long way in keeping you and your family cool and help avoid those stressful emergency calls in the middle of a heat wave in the summertime. 

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