What Makes an AC Compressor Go Bad?

If an air conditioning (AC) system is not running properly, any number of serious mechanical issues can be to blame. These issues range from exposure to frost and the age of the compressor unit to serious damage to the internal wiring. In most cases, a repair technician should be called to inspect the unit.


There are several signs to look for if you suspect that an air conditioning compressor unit is in danger of failing. These include the compressor motor operating with more noise than usual, including buzzing and clanking sounds. Also, if a compressor has electricity but the motor and cooling fan are not running, this is a sign that there is a problem with its starter component.


Sometimes the compressor motor can "burn out," which means that the wiring inside has been burned or shorted out or the windings have been disconnected. In this case the motor will need to be replaced.


When an older air conditioning compressor has not been used for some time, or is low on oil, the compressor can become damaged and "seized." This means that the pistons can't run correctly in the cylinders.

About the Author

Erik Arvidson has 12 years of professional writing experience, including six years as a senior reporter at the Massachusetts Statehouse for several suburban dailies, and most recently as PR Manager of a telecommunications company near Boston. He received a Bachelor of Arts degree in English/communications from North Adams State College.