Why Wall Unit Air Conditioner Freezes up

Outdoor Temperature

• If the outside temperature is very cold and the wall unit air conditioner is set to "Cool," the cooling element or coils might freeze. When the element freezes, ice builds up and prevents the air from flowing out to the vents or louvers. Condensation forms inside the unit due to the outside and inside temperature dynamic because the air conditioner unit can't cool any lower than a designated thermostat setting, which is 60 degrees Fahrenheit on most models.

Thermostat Setting

• The thermostat can aid in defrosting the internal cooling element. When the coils are defrosted, the unit functions properly again. Press the up directional button on the remote control or on the unit's front panel to increase the thermostat to a high number. The average peak thermostat setting for an air conditioner unit is 86 degrees Fahrenheit. The warmer air flows through the unit and coils, melting the accumulated ice.

Fan Setting

• You can enhance the melting power of the high temperature setting by increasing the fan speed. Press the "Mode" button on the remote control or the AC's front panel until you reach "Cool" or "Cool High." Press the "Fan Speed" button on the remote control and the unit's front panel repeatedly until the fan speed reaches "High," which allows warm air to flow rapidly through the cooling element and expedite the defrost process. You'll know the ice is melting when you feel air blowing through the louvers or vents, which occurs approximately 30 minutes after the thermostat and fan settings are set.

Power

• When you want to turn the unit off to defrost it, that will work just fine but might take a little longer than using the internal fan and thermostat. Press the "On/Off" button on the remote control or on the unit's control panel. The indicator lights and the fan will shut off. To avoid electrical damage, unplug the unit from the wall outlet, and allow the air conditioner to melt for approximately one hour. Before you turn the unit on, inspect the interior for condensation. If you see liquid anywhere, allow the appliance to dry out completely before you turn it on.