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7 Signs Your Air Conditioner Capacitor Has Gone Bad

The short answer is you may have a failing AC capacitor if you are experiencing any of the following symptoms:

  • Your AC system isn't blowing cold air
  • You hear a humming noise coming from the outdoor unit
  • Your monthly energy bills are rising unexpectedly
  • Your air conditioner will shut off unexpectedly
  • Your AC unit doesn't come on at all
  • You smell something burning from the outdoor unit
  • Your air conditioner has become too old

It's not always easy to tell when your air conditioning system is suffering from a bad capacitor. But when you do find yourself with a faulty capacitor, it can lead to a higher energy bill and costly repair if left untreated. So, it's important to know how to check for warning signs and handle the situation if it comes up.

What Is An Air Conditioner Capacitor?

If you're unfamiliar with the components of your AC unit, every AC system has a motor, and all motors are equipped with a capacitor. This device charges and starts the motor, allowing the cooling cycle to begin by initiating the fan blades' movement when the AC turns on.

The cool air you enjoy on a hot summer day is all thanks to the capacitor doing its job and keeping your air conditioning running. You can run capacitor tests to ensure that the cooling is operating smoothly on a routine basis.

When an AC issue arises, it likely has to do with the capacitor inside most models' AC units. An old capacitor is more likely to break down over time, while bad capacitors require more energy to run. When the problem persists, it's time to consider calling the HVAC experts to perform air conditioning repair service and replace the AC's capacitor.

This brief overview of the most frequent bad AC capacitor symptoms to look out for when evaluating your AC unit can help you find the right replacement later on.

1. Air Conditioner Not Blowing Cold Air

When the capacitor is bad, warm air blowing through your vents and not cold air is one of the first signs of trouble. You can try turning your condenser unit on and off again, but you may be dealing with a failing capacitor if the problem persists. This can happen when the air conditioning system short circuits or experiences damage due to the elements.

Replacing your air conditioning capacitor could come at a high cost, but contact a professional HVAC company to test your AC unit before proceeding with repairs or replacement. Proper AC service can determine the root of the issue before any other steps are taken.

2. Humming Noise from Outdoor Unit

A sure sign of a bad AC capacitor is a humming sound from within the access panel. Any humming noises indicate a problem with the air conditioning system or the components of the AC unit. Try turning the power on and off again to see if it was a one-time issue with the motor or a recurring problem.

If the capacitor is bad, the problem will persist. Call the HVAC experts to test your air conditioning system and see if any components require replacement. A professional will provide a free estimate before discussing the AC capacitor replacement cost.

3. Rising Energy Bills

Another one of the most prominent bad air conditioner capacitor symptoms is an increase in your electric bills. When an air conditioning capacitor is bad, the ac takes more power to run. Your HVAC system will strain itself to provide cool air, lowering the unit's voltage rating and overall effectiveness.

Lower voltage will waste energy and money if left untreated. Restore your unit to its full power by contacting professionals to repair or install a replacement capacitor. A new capacitor will have your HVAC system running smoothly again, without any of the bad AC capacitor symptoms slowing it down further.

4. Air Conditioner Turns Off Randomly

If your AC shuts off without warning, your capacitor is bad. The air conditioning system should never shut off on its own and will need to be looked at by a professional if a trip to the hardware store doesn't work out. The unit may short circuit now and then, but continuous problems need to be evaluated.

The condenser unit dispels the hot air to keep your home cool, but it can't operate properly if the air conditioning turns off randomly. Of all the most common bad capacitor symptoms, having a faulty air conditioner turn-off is the most concerning.

5. Air Conditioner Does Not Turn On

Another indicator of a bad capacitor is when the system takes a while to turn on or won't turn on at all. This is a clear sign of an issue with the air conditioning system and likely involves the capacitors. You can remove the side panel for a better look.

For these situations, it's usually best to have a professional replace the capacitor. Double-check the voltage before you call a professional to provide them with detailed information. From there, they'll be able to assess the situation and determine the best course of action.

6. Burning Smell From Outdoor Unit

You never want to encounter a burning smell from your air conditioning system. This is a strong sign that your system requires repair or replacement to work properly again. The capacitor symptoms may be due to a thin object obstructing the system, normal wear and tear, or overexertion of the system.

If the motor overheats, you'll smell something burning. The bearings in the system will wear down over time, which can cause the issue. Some quick fixes, like lubricating the bearings, can temporarily help resolve the problem, but replacement is the best option for a more permanent solution.

7. Age of Your Air Conditioner

The older your air conditioning is, the more likely it will break down. Capacitors don't last forever, and an older one is subject to burning out. An older system will experience malfunctions for one reason or another, and unfortunately, the only real solution is to replace the system entirely.

How Long Do AC Capacitors Last?

On average, AC capacitors last up to 20 years with regular maintenance. However, the lifespan of the capacitor also depends on the brand and the quality of the materials used.

If you find yourself needing a replacement, don't cut corners. Research which components will work best for your air conditioning.

Will My AC Unit Still Work with a Bad AC Capacitor?

While your AC will still work with a bad capacitor, it will struggle to function correctly. Eventually, the system will stop working altogether. Extended use can cause further damage internally.

We recommend contacting a professional to handle the repairs so that you don't risk any damage to your air conditioning.

Need Your AC Capacitor Replaced? Call ARS/Rescue Rooter

Now that you know what to look for in a bad AC capacitor, who can you call for assistance? ARS/Rescue Rooter specializes in repairing your air conditioning so you won't have to sweat it.

Contact us today to schedule service and receive a free estimate. Our team is dedicated to quality customer service and strives to meet your expectations. We look forward to hearing from you!

Searching for more knowledge to boost your indoor comfort? Sign up for our email newsletter and you'll receive expert tips and advice from our HVAC & plumbing pros. Plus when you sign-up. you'll be entered into a drawing to win a FREE 50 Gallon Gas or Electric Water Heater!

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