AC Repairs 101: Know the Symptoms of a Bad AC Capacitor

January 11th, 2022

One of the most common reasons for an AC performing below optimal level is a bad AC capacitor. The capacitor is what charges and starts your AC’s motor. Therefore, to prevent greater damage, it is crucial for homeowners to identify the first symptoms of a bad AC capacitor. By replacing the capacitor on your AC unit, you’ll extend its lifespan and keep your house cool and comfortable through every season.

AC repairs

Most common first signs of a bad AC capacitor:

1. Vents Not Blowing Cold Air

Typically, one of the first things homeowners notice is that cold air isn’t blowing from the vents; this is one of the most apparent bad AC capacitor symptoms. Turn your cooling system on and off to see if this resolves the issue. If you continue to feel warm air from the vents, contact a licensed HVAC professional for troubleshooting your bad AC capacitor.

2. Higher Than Usual Energy Bills

As capacitors wear down, the other components of your HVAC system are required to work harder—this increases your energy bills. If your energy consumption is higher than usual, an underpowered capacitor may be at fault. Often, as capacitors wear down, energy bills slowly creep up with or without you noticing. Therefore, monitoring your energy consumption is essential to compare your statements from years past.

3. Unusual Compressor Humming Noises

When you power up your AC unit, listen for a slight humming noise from the compressor. If you hear this, your capacitor may be struggling to start your AC’s fan motor. In conjunction with a delay in turning on, this hum almost guarantees that your capacitor is heading for failure.  It’s essential to immediately switch out the capacitor before the compressor or fan is damaged. Contact a local HVAC professional before your capacitor entirely breaks down.

Infographic Explaining AC Repair

4. Older HVAC System

As a cooling system ages, it requires maintenance and repairs to maintain optimal performance and keep your home cool and comfortable. If your system is older, note that your AC works sporadically and sometimes struggles to start operating, and this could be another indicator of a faulty capacitor.

Infographic explains AC repair problems

5. Independent Shutdown

If you start to notice that your air conditioner turns off randomly and doesn’t cycle correctly, there’s a good chance that you have a damaged, deteriorating, or faulty capacitor. A healthy unit will turn off during an auto phase on your thermostat, but it shouldn’t turn itself off during regular operation.

6. Sluggish Turn On and Operation

If your unit does not turn on immediately, this likely is a symptom of a bad capacitor. Additionally, if the air conditioning typically takes several seconds to kick in once powered on, this indicates a weak capacitor. An HVAC technician will be able to tell you if your system requires a new capacitor or not.

7. AC is Inoperable

If your air conditioner isn’t turning on at all, there can be various issues. A faulty or failing capacitor is one of the best outcomes because a more significant problem could require you to replace your condenser unit entirely. A licensed service technician should run diagnostics to determine if the capacitor is the cause of this malfunction.

 

In addition to saving money by not having to replace the entire unit, you will experience less time without air conditioning which will increase your comfort and decrease the risk of mold growth while the AC is off.

Do You Have a Bad AC?

Island Comfort has been providing excellent HVAC services to Oahu and Kauai, and our dedicated team of professionals understands the unique demands on AC systems in these humid conditions. We’ll diagnose whether or not a replacement capacitor will help resolve your problem to keep your home cool and comfortable year-round.

Contact us today to find out how we can help you identify and solve any air conditioning system issues you’re experiencing!