How to Find Your AC Capacitor
The location of your cooling system’s compressor determines where its AC capacitor can be found. The AC capacitor is important because it:
- Maintains a consistent flow of electrical current
- Maximizes AC efficiency for the best possible performance
- Protects the AC system by preventing an electrical voltage drop that could damage the unit
There are several types of home air conditioning systems, and all of them have compressors. (One exception might be portable air conditioners and fans that operate without compressors.)
The most common U.S. home air conditioning systems include:
- Central air
- Ductless mini-split/floor-mounted
- Geothermal heat pump
If you wish to locate your AC capacitor, you must first shut off the power to your cooling system. To check the capacitor itself, the wiring must be disengaged and all voltage drained.
Your home central air system’s outdoor unit is usually located on the side or back yard. The outdoor system is often called the “condenser.” Inside are the circuit board, compressor, and heat exchange coil. The AC capacitor is inside the compressor. It’s a cylinder-shaped component that looks like a big battery. To find it, you’ll need to remove the unit’s side panel.
Ductless mini-split (aka floor-mounted ACs)
Ductless mini-split system condensing units are also located outside the home. The compressor’s AC capacitor can be a small, square-shaped (“run cap”) component or a large and cylinder-shaped (“fan/motor cap”).
The best thing about these ACs is they don’t take up a lot of space and it’s easy to change the filters. Easy access makes them great for people with respiratory challenges or those that desire above-average IAQ (indoor air quality).
The geothermal system has a compressor, condenser, and an evaporator. The compressor and AC capacitor are in the outside unit. On geothermal heat pumps, AC capacitors are the components that fail most often and require repair or replacement.
Geothermal heating and cooling systems don’t convert electricity or fuels into hot/cold air. They have a heat pump located inside the house and a tube or pipe buried in the ground outside your house. The compressor circulates a water-based liquid that acts as a “heat exchanger.” It either retrieves or releases the air’s heat.
One reference said it’s safer to buy a new window air conditioner than to try to locate the AC capacitor in a window air conditioning unit. The outdoor portion of the window unit contains a compressor, condenser, condenser coil, and fan. It’s connected to the indoor part by a copper refrigerant tube. AC capacitor testing can only occur once the power has been shut off. To check the capacitor itself, the wiring must be disengaged and all voltage drained.
Don’t DIY: Call Country Air of Tomball
When homeowners tackle DIY (do-it-yourself) projects, it’s a terrific opportunity to learn more about your home and how things work. Most home repair projects take longer but can save money if you do them right the first time. Quite simply, replacing an AC capacitor is not a DIY project.
Before you buy a replacement, knowing which capacitor your system needs is critical. Capacitor systems use either start-or-run, dual-run, or blower capacitors. Heat pumps use specially designed capacitors.
No HVAC (heating, ventilation, air conditioning) company will recommend you attempt an AC capacitor repair or replacement.
- If fire/property damage occurs because of DIY/handyman HVAC work, your insurance can deny coverage.
- Injury or death is a much higher risk with DIY/handyman capacitor replacement project.
- Manufacturers’ warranties on all HVAC components/parts can be voided.
Country Air is North Houston’s trusted heating and cooling company. We’ve proudly served Montgomery and Harris County families for 45 years and our technicians care about quality and professionalism in everything we do. Guaranteed.