Call in an HVAC Professional to Fix a Faulty AC Compressor

If the compressor in your central air conditioner or heat pump is overheating, the appliance may continue cooling temporarily but it’s only a matter of time before you’re stuck with a broken AC or heat pump. Unfortunately, a busted compressor is one of the most expensive fixes for a central cooling system, and among the leading reasons that homeowners decide to upgrade to a new system.

What Role Does a Compressor Play in Your AC?

Without getting too technical, the compressor in a central air conditioner or heat pump serves two purposes. Located in the outside unit of a split-system AC, along with the condensing coil and fan, the compressor pumps refrigerant through heat-exchange coils and lines. It also places gaseous, heated refrigerant under pressure in the condensing coil, which converts the refrigerant into a liquid. When this happens, heat energy (extracted from indoor air during the evaporation/cooling process) is released into the surrounding air outside. If the compressor is malfunctioning or not working at all, this will impede or stop those essential functions.

You may be able to make an educated guess on what’s causing your central AC or heat pump’s compressor to get too hot, but unless you’re certified and experienced working with complex HVAC equipment, working hands-on with the equipment is a task left to a professional.

Troubleshooting a Malfunctioning Compressor

Following are some common causes of AC compressor problems:

• Overheating that causes high head pressure may be the result of dirty condensing coils, a defective condenser fan, too much refrigerant, or some other heat source close to the condenser, such as a dryer vent.

• An electrical problem may result in compressor overheating. This may be high or low voltage or a power spike. It can be related to something external such as issues with an electrical transformer or the power grid, or something internal in the home’s electrical system.

• Something called “high superheat” may be caused by insufficient refrigerant in the AC system, a kink or other impediment in the refrigerant line, a defective metering component, or a hot-water pipe that’s too close to the compressor.

• An AC system that’s short-cycling (stopping and starting frequently) may also result in an overheated compressor. Common causes of atypical short cycling include a clogged air filter, dirty evaporator coil, or defective capacitor or metering device.

If your central air conditioner malfunctions – either no longer issuing cool air or halting operation completely – there are a few simple steps you can take before calling in a professional. Check the air filter and change it if it’s dirty, inspect vents and registers to make sure they aren’t blocked, and check for any obvious problems with your air ducts. If the AC stops entirely, check the breaker box to make sure the circuit hasn’t tripped. And of course, look at the thermostat to see that it hasn’t been switched to “heat,” turned off, or the temperature setting raised to a higher level than the temp in the house.

If none of these troubleshooting methods fixes the problem, call your trusted Cincinnati AC repair contractor.