Warning Signs Your AC Capacitor Is Failing

Don't Let AC Capacitor Failure Disrupt Your Business. Learn The Warning Signs Like Intermittent Operation, Blowing Fuses, Strange Noises, And High Utility Bills

As a business owner or property manager, a fully functioning HVAC system is essential to providing a comfortable environment for your customers and tenants. But when the air conditioning capacitors that help run the system fail, it can lead to disruptive and expensive breakdowns if not addressed promptly.

Knowing the warning signs of capacitor failure allows you to catch problems early and make replacements before serious issues arise. This preventative maintenance approach saves money compared to emergency repairs after a failure brings your AC system to a halt. When is the best time to schedule fall maintenance?

What Do Capacitors Do in an AC Unit?

Before diving into the failure signs, let’s quickly cover the role capacitors play in an air conditioning system.

The AC capacitor is a small device that stores electrical charge and helps regulate current flow. The most common capacitors are start and run capacitors.

Start capacitors provide a boost of power to start the compressor on initial startup. The run capacitor then keeps the compressor and condenser fan motor running smoothly once the system is operating.

Without this stable power regulation from the capacitors, the AC would not be able to turn on, blow cold air continuously, or run efficiently.

Given their vital importance, any indication of capacitor failure must be addressed swiftly to avoid system breakdown. Contact J&D Mechanical Services

Intermittent Operation Points to a Failing Capacitor

One of the most common early signs of a bad AC capacitor is intermittent operation. This is when the unit starts up and blows cold air as expected, but then shuts off after a short time.

To the end user, it seems the AC is working at first but then just stops for no reason. What’s actually happening is that the faulty capacitor stops providing consistent power to the compressor and fan, causing them to cut out until the capacitor charges again.

I’ve seen this happen when a failing run capacitor reaches the end of its lifespan. The AC runs fine for 10 or 15 minutes but then stops once the capacitor can no longer deliver stable power. A quick capacitor replacement restored normal operation.

Intermittent failures like this are frustrating and disruptive. But thankfully replacing the old capacitor is an affordable repair that gets the system running right again.

Blowing Fuses Signal a Short Circuit

Does your AC service panel keep blowing fuses when you try to turn on the system? The most likely culprit is a short circuit from a bad capacitor.

As capacitors fail, they can create shorts in the electrical system. This puts excessive load on the fuses, causing them to blow continuously. You may also see other electrical issues like flickering lights when the AC starts due to the temporary power dip from the short.

Thankfully a fuse blowing is doing its job to protect the rest of the electrical equipment from damage. But you don’t want to just keep replacing blown fuses over and over. Get a technician out to diagnose the short and replace the faulty component causing it, likely a capacitor.

Strange Noises Point to Compressor Issues

Hearing odd noises like humming, buzzing or clicking when your AC runs can indicate capacitor problems that are impacting the compressor.

The compressor contains non-moving parts like the windings that require consistent electrical power to function properly. If they receive fluctuating power from a bad capacitor, it creates vibration and noise issues.

The noisy symptoms may come and go if the capacitor is still somewhat functional. But any strange new sounds from the AC are telling you the capacitors need attention. And compressor damage can occur if the issues persist.

The AC Fan Works, But Cooling is Intermittent

Here’s another common intermittent symptom of capacitor failure – the condenser fan motor turns on but cooling starts and stops.

This points to a failing run capacitor that is only providing power to the fan motor intermittently. With no power, the compressor won’t run and cooling stops. But the fan keeps working which makes it seem like the AC is still on.

Like other intermittent issues, the root cause here is the run capacitor is unable to deliver stable continuous power. Replacing it restores the smooth unified operation between the fan, compressor and capacitor.

High Utility Bills Indicate Inefficient Operation

Capacitors help a system run at peak efficiency. So if your AC is using a faulty capacitor, your monthly bills will likely reflect the wasted energy.

Significantly higher than normal utility costs when running the AC can indicate the system is working much harder than it should to try to maintain the target temperature.

There are other possible causes like refrigerant leaks or other mechanical breakdowns. Your technician can examine the capacitors and determine if failure is leading to the efficiency issues. Replacement can often lower bills back to normal.

When to Call in a Professional

While the signs above may help you identify capacitor issues, I don’t recommend trying to replace them on your own unless you are highly experienced with HVAC repair. The electrical components require care when handling to avoid damage or injury.

Your best move is to schedule an inspection with an HVAC technician as soon as you suspect capacitor failure. They have the proper training and equipment to diagnose issues safely.

To stay ahead of problems, it’s also wise to have annual tune-ups done on your AC system. The technician will check all components, including inspecting the capacitors for signs of future failure.

Don’t Let Small Issues Turn Into Big Problems

Failing capacitors in your air conditioning system may start out causing only minor intermittent operation. But ignoring these early warning signs allows the issues to escalate into complete breakdowns that disrupt your business and require costly repairs.

Stay alert for any of the symptoms covered in this article so problems can be addressed before the capacitors totally fail. Replacement of bad capacitors is an affordable fix that prevents much larger headaches down the road.

Your AC capacitors are easy to overlook but critical to the system’s healthy operation. Keeping an eye out for signs of failure allows you to be proactive with maintenance and avoid major issues.