Last updated on March 10th, 2024 at 03:16 pm

Well without seeing the unit, there’s a small handful of things that could go wrong with the window unit air conditioner.

Is it dirty?

Believe it or not the number one cause of window unit air conditioner malfunction is dirty or grimey coils or condensers. The symptoms range from the unit smelling musty or blowing dirty air to the condenser not turning on at all even when the a/c unti is supposed to turn on (request for cooling was sent by the thermostat.) The fix is simple: clean the coils. Take a vacuum and clean the coils.

Is it leaking?

Most window air conditioner units are also designed to be dehumdifiers by nature – they remove moist air. Also the nature of a condenser coil in your air conditioner (taking warm air and making it cool) produces water vapor (condensation) as part of the process. This normally collects ont he coils and drips down to the bottom of the unit. When A/C units are positioned and installed correctly, the water drips from the unit to the outdoors naturally. If water or liquid is dripping indoors, it means the unit is not installed correctly. Typically, A/C units are designed to sit in a window at an angle of a few degrees, just enough to pool water and force it to the tilted end – outdoors.

The solution is simple: readjust the unit so it “leaks” or drips outdoors. The chances are very slim that the condenser cracked or is leaking fluid. Freon, the material used in many coils, is a gas and not a liquid. Still, if the liquid is not clear, you may want to consult a professional for a second opinion, or just discard the unit and get a new one.

Fan doesn’t operate.

Check the thermostat. Should the fan turn on? Next step would be to unplug the unit and spin the blades manually. If it doesn’t spin easily, check to make sure there isn’t hair or other material tangled on the shaft. You may also need to lubricate it slightly to make sure it spins. It might also be a blown resistor on the motor, or even the motor might also be bad.  If you have electronics experience and working with high voltage, you can run a voltmeter across the motor when the fan has power to see if it is getting power. If so, the fan is bad. Otherwise, check the internal fuses or the line running to the fan. It might be a bad relay or switch.