Glacier In Your Mechanical Room? How To Deal With Frozen Evaporator Coils

One common problem during the cooling season occurs when the evaporator coils inside your home freeze over. When ice forms on the coils, it can completely cut off the air flow to your home, which will prevent your unit from cooling your home, but it can also cause damage to your AC unit. In most cases, frozen coils are a problem that you can take care of on your own.

Step One: Defrost the Coils

On a hot day, you may want to get the ice off of your coils as quickly as possible. Hacking away at the ice with an ice pick, screwdriver, scissors, or some other sharp object might seem like the best way to remove the ice quickly; however, you should never take a sharp object to the ice. It is too easy to poke a hole in the thin metal fins that make up the coil and then you have a repair that should only be handled by a federally certified technician.

Instead, you should turn your thermostat to the the fan position. Place towels and a bucket under the evaporator unit to catch meltwater. If you want to speed up the process, you can remove the panel that covers your coils and use a heat gun or hairdryer to melt the ice. 

Step 2: Deal with the Cause of the Indoor Glacier

Ice does not form on a properly functioning AC unit. Thus, if you see ice, you have a problem that needs to be dealt with. Ice forms when there is not enough air flowing over your coils; however, a loss of airflow could occur for any of the following reasons:

1. A Dirty Filter—Check your filter, and if it is dirty replace it. 

2. Dirty Coils—If too much dust builds up on your coils, the dirt can block off the flow of air through them. Clean your coils with a plastic fin comb and a stiff-bristle brush. Never use a metal-bristle brush as it can damage your coils. 

3. Blocked Return Registers—Not every vent in your home serves the purpose of allowing cooled air to enter your home. You should have a larger vent or two that your system uses to pull air to the evaporator unit. If you block this register with a piece of furniture, a stack of clothes, etc., you can cut off the flow of air. Move the blockage to improve airflow. 

4. Closed Vents—Sometimes homeowners will close vents to prevent air from going to certain rooms. If you shut off too many vents, air will have nowhere to go once it leaves the evaporator. As a general rule, you should not close off more than one or two vents. 

5. Internal Malfuntion—If you take the above steps, and everything checks out, you likely have a broken fan or a problem with the internal workings of your system. Either way, it is time to call a professional. 

Taking the time to troubleshoot iced over evaporator coils can save you money. Often the repair is well within the range of even a timid do-it-yourselfer, but if you find that your best efforts are not enough, you should feel confident calling an AC repair technician (like those at Hallmark Service Company) to take over the repair.