What Causes Your House AC Unit Fan to Stop Turning & Freeze Up?

During hot weather, a functioning air conditioning system is necessary for comfort and health reasons when it comes to children and the elderly. Regular maintenance and check-ups conducted multiple times a year help ensure your AC system functions optimally, and allow you to pinpoint future problems. An AC fan that stops turning and freezes up is a problem in itself but can also signal another potential malfunction in your home's air conditioning system.

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Fix air conditioner fan problems

Temperature Is Off

When a fan is set in "Auto" or "On" positions, the fan should turn and blow cool air into the building and turn off when it is no longer needed, because the room has reached the desired temperature according to the thermostat setting.
The temperature must be set lower than room temperature for the air conditioner to cool and the fan to work. The indoor air temperature varies around the thermostat's set point, says Inspectapedia. The mechanism contains an internal temperature sensor that compares the ambient air temperature at the thermostat to the temperature set by you, and turns the cooling equipment on or off as appropriate, says the website. Check your wall thermostat, usually mounted in the living area, to make sure it is in the "cool" position. Set the temperature below the surrounding air temperature to activate the fan again.

Safety First

The fan may switch off unexpectedly if the air conditioning unit has detected a safety issue, such as overload of the electric motor. If the motor is overworked or overheats, a button, called an overload reset button, will pop out indicating that an internal electric safety device was tripped, says Inspectapedia. This shuts the motor off. When the air conditioning fan has cooled sufficiently, you can press down on the reset button to start the motor again. If the button won't stay pressed, it may not be cool enough to restart safely, or another malfunction exists.

Fan Belt

Some air conditioning systems require a fan belt to connect the blower motor to the fan. A fan belt may come loose or break, causing the fan to stop turning. According to home Heating System Help, an air conditioner fan belt may become misaligned or worn out, in which case it has to be replaced. Continuous squealing noises prior to the fan stopping signal there is a problem with the fan belt.