A frozen evaporator coil can shut your air conditioning system down. Your AC might short cycle and trigger the safety switch to shut down the equipment or your AC might run continuously when there is ice on the evaporator coil. Ice can form on the coil because it's always wet with condensation. There are usually two causes: a clogged filter and low refrigerant. Here are common AC system repairs for ice on the evaporator coil.

When A Clogged Filter Is The Cause

When you see ice on your evaporator coil, shut the AC off first thing. The ice needs to melt so the AC can be repaired. It may take hours for the ice to melt, but you may want to call an air conditioning repair company and let them know your problem so they can offer advice.

They may want you to check the filter and change it if it's clogged. That might be enough to get your AC working again once the ice is gone — unless the coil got dusty and grimy due to the dusty filter. If the coil is dirty too, the repair technician has to clean it before turning the AC back on. Once the ice is gone, the repair technician can inspect the coil to look for grime and scrub it if necessary.

When Low Refrigerant Is The Problem

Low refrigerant is a more serious matter. The AC system repairs for this might include patching up a hole in the evaporator coil in addition to adding refrigerant. The repair technician can measure the amount of refrigerant in the system to tell if it's low.

If so, they'll need to look for a leak. Tightening a connection might fix the problem, but if not, they'll need to patch the hole before they can fill the refrigerant back up. This repair might take a while, but it's necessary when the refrigerant is leaking or all the refrigerant could leak out and your AC wouldn't work at all.

It might take several hours for the ice to melt off of the evaporator coil. During that time, the repair technician might work on the refrigerant issue. Your AC might work again once the ice has melted, but ice will just build back up again if the reason for the ice buildup is not corrected.

It's stressful on the equipment to run it when there is ice in the system, so shut your unit off and call an ac repair service when you see ice in your air handler or the condenser outside.