What Makes a Refrigerator Run Capacitor Go Bad?

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Electrical problems are the main reason that can make your refrigerator's capacitor go bad.
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You rely on your refrigerator to keep your food cold and fresh. If any part of the appliance stops working, it can be extremely problematic. One refrigerator part that could cause a functionality problem is the run capacitor. Electrical problems are the main reason that a refrigerator capacitor might stop working properly. This requires immediate repairs to ensure the functioning of the appliance.


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What Is a Run Capacitor?

The run capacitor of the refrigerator is an important component in its start up relay. The run capacitor assists the refrigerator compressor, which should only run for a few minutes in any given hour. If it runs longer than that, the compressor can overheat or its motor can burn out.

The PTC, or positive temperature coefficient, is another part of the start up relay system. If the PTC is overheating or indicates too much heat, the run capacitor will turn the compressor on. The heat from the PTC is what signals the refrigerator capacitor to turn on.


Given its essential role in keeping the PTC and compressor running, it's easy to see why having a functioning run capacitor on your appliance is critical.

Refrigerator Capacitor Electrical Issues

An electrical problem is often the main cause of issues with the refrigerator's run capacitor. Wiring may become disconnected over time, or circuitry can go bad. Without this functioning system, the PTC won't have backup and the compressor may not run properly.

You can attempt to check the run capacitor for electrical failure on your own using a multimeter to test the refrigerator start relay. However, if you are not familiar with how to use a multimeter or have little experience with electrical work, you should not attempt this sort of troubleshooting on your own. Refer to your owner's manual for more information about what the electrical reading for the run capacitor should be when you do use a multimeter.


Repairing a run capacitor also requires manipulation of wiring and other electrical components. If you do decide to undertake this fix or replacement on your own, be sure that there is no power to the refrigerator. The best way to verify that the unit has no power is to both unplug it and turn the circuit off at the breaker box. This extra step will protect you if you accidentally forget to unplug the appliance.

Troubleshooting a Run Capacitor

Knowing what makes a run capacitor go bad is useful, but how will you know if that's the problem? Fortunately, a run capacitor that is failing often exhibits a tell-tale clicking noise that you can use to pinpoint the problem. The part may click on start up or on shut down. This is one of the main symptoms of a bad motor run capacitor.


This part is located in either a white or black box near the compressor at the back of the refrigerator. With the help of another person, you can pull the refrigerator safely away from the wall and try to listen for this clicking noise. If you hear it, and it seems to be emanating from the box, you can be fairly certain the issue is the run capacitor.

One way to avoid issues with the run capacitor is to keep the surrounding area clean. Vacuum behind your refrigerator frequently, and use a damp cloth to wipe down any standing dust or debris, which should only be done when the unit is unplugged). Your refrigerator also needs a bit of space between itself and the wall to allow for proper air flow, so don't push the appliance backwards too tightly.



Danielle Smyth is a writer and content marketer from upstate New York. She holds a Master of Science in Publishing from Pace University. She owns her own content marketing agency, Wordsmyth Creative Content Marketing, and she enjoys writing home and DIY articles and blogs for clients in a variety of related industries. She also runs her own lifestyle blog, Sweet Frivolity.