You're sitting inside your comfortable home, when you hear a high-pitched squealing that reminds you of the sound an angry pig makes. You look outside, wondering who let a pig loose in your yard — but what you find is that the sound is actually coming from your air conditioner! What could be making your air conditioner sound like an angry pig? There are actually a few possibilities.

Torn Belt

Older air conditioners, and even some new ones, have motors driven by belts, much like the motors in cars. The function of the motor is to push the cooled air out into the home. If the belt starts to fray or develops a partial tear, which is pretty common as a motor ages, you might hear a squealing noise coming from the motor. This noise may come and go as the belt goes around and around. Luckily, your air conditioner repair company should be able to simply remove the damaged belt and install a new one. Belts are inexpensive and pretty easy to install.

Worn Bearings

Ball bearings in your air conditioner make sure that various components of the unit move smoothly over one another. Due to friction over time, they can start to flatten on one side, and that can result in a consistent, high-pitched squeal as the air conditioner continues to run. Usually, when a worn ball bearing is to blame, the squealing will be worst when the AC unit first starts and when it stops, since this is when there's the most friction on the ball bearings. Ball bearings can be replaced, but doing so often requires disassembling the motor. If the air conditioner is already old and having other issues, you may just want to replace it.

Blocked Duct

Does the squealing actually sound like it's coming from within the walls, not from the air conditioner? It might have a whistling sort of quality to it. Chances are that this noise is caused by a partially blocked duct. Air is being forced to push past the partial obstruction in the duct, and since it speeds up through the compressed space, it makes that squealing noise. Try removing the vent closest to the place where the noise is coming from. If you can see the item blocking the duct, you may be able to reach it and remove it. Otherwise, you might need to have a professional come remove the obstruction.

Your air conditioner should sound like a happy fan, humming along throughout the day. If it's squealing like an angry pig, something is amiss -- probably one of the issues above. For more information, reach out to an air conditioning repair company such as Northwest  Heating &  Air Conditioning Inc.