Why Does My Air Conditioner Have Ice Around the Wires?

Broken Thermostat

• A non-functional thermostat causes the cooling element compressor to run continuously without the fan, which causes the unit to freeze. Not only does it freeze, cold air circulation ceases if the fan shuts off, which can damage the unit. One way to test the thermostat is to lower it so that the thermostat setting is lower than room temperature. After the fan and the compressor both start running, raise the thermostat to a level above room temperature and listen for the compressor to turn off. If the compressor continues to run, then the thermostat is broken and needs a replacement or repair.

Reverse Fan

• Some air conditioner fan motors feature a reverse switch, which allows you to determine which direction the fan blows, like an overhead fan in a room. If the fan blows in the opposite direction, this causes the cooling element to freeze and prevent cold air from circulating through the room. You can adjust the fan in two ways; you can remove the necessary panels to get to the fan motor and reverse the fan with a flip of the switch, or, if the motor has no switch, turn the unit off, uninstall the fan and remount it facing the opposite direction.

Blocked Fan

• A blocked fan has much the same effect as a reverse fan -- without the fan to vent the cold air produced by the cooling element, internal components freeze. A fan can become blocked by mold that grows around the fan motor gears or by debris, such as a plastic bag accidentally sucked into the intake grille. After the removal of fan compartment panels, inspect the fan for debris or grime. Remove the debris carefully or clean the grime away before testing the fan again. If the fan still fails to turn, the motor might be damaged and requires repair.

Cold Outside Temperature

• If the outside temperature is lower than the lowest thermostat setting on the air conditioner unit, then the clash between temperatures might cause condensation, which then freezes on the cooling element. Should the unit freeze due to low outside temperatures, you can shut the unit off to allow the unit to thaw. To avoid possibly damaging internal electrical components, unplug the unit. Once the unit thaws, you can plug it back in, turn it on, set the thermostat to a higher setting and lower the fan speed.