What To Do When Your AC Unit Freezes Up

When an AC unit freezes up, it can be a sign of a potentially significant issue. Learn how to identify, prevent and fix this problem below!

Signs Of A Frozen AC Unit

Keep an eye out for the following signs indicating your AC unit may be frozen.

Refrigerant Line Frost

If you see frost on the copper lines, then it’s very likely your AC unit is freezing up. When frozen, frost will build up and show on the copper that comes out of the system. The worst case scenario here is when a full block of ice develops. This will undoubtedly take a decent amount of time to thaw out.

Producing Minimal Amount Of Cold Air

This is the most obvious sign of a frozen system. In this case, there will be a lack of air coming out of the vents, causing your home’s temperature to rise. What happens here is the ice in the coil restricts airflow and this causes the supply air to trickle out of the vents.

How To Fix A Frozen AC Unit

Follow these simple steps to fix your AC system.

Step 1. Shut Off The System

The first thing to do when you suspect your unit is freezing up is to immediately deactivate the system. More ice will form as long as your unit continues to cool. Either turn the cooling off at your thermostat or pull your disconnect breaker to the outdoor unit only.

Step 2. Turn Thermostat Fan Setting To On

Turn the thermostat setting to “on” so that your fan can continue to blow air over the coil. This warm air in the house will naturally defrost the frozen coil. You can also turn the heat on to speed up this process.

Step 3. Check For Any Water Damage

When the coil begins to thaw, the water will collect inside the system, typically overflowing. This is because there is more water collected than can drain out. Water damage can occur at this time if your primary drain pan overflows.

How To Prevent Your AC Unit From Freezing Up

The simplest way any homeowner can prevent a frozen AC system is by continuously inspecting and replacing the air filter. A dirty filter will ultimately reduce airflow and cause the refrigerant cycle to lose the overall balance of air and line pressures. Most of the time compromised refrigerant lines cannot be repaired, meaning a complete replacement is necessary.