You’re probably used to hearing a steady, low humming sound when your air conditioner is operating, and this is perfectly normal. However, if your humming air conditioner is producing more of a loud buzzing noise, it can be a sign of a problem in the system that needs further investigation.

What Causes Concerning A/C Humming Sounds?

There are a number of potentially-serious issues that can produce a buzzing or humming noise in a central A/C. The underlying cause can pose a danger of equipment damage that requires a costly repair or equipment replacement, or it may put your family’s safety and well being in jeopardy. If you hear a loud humming/buzzing noise coming from any of the following areas, shut down your cooling system right away and call a reputable HVAC pro for help:

• Indoor evaporator coil. If you hear unusual humming from inside the air handler, the evaporator coil may have iced up. Once the A/C is shut down, place a container under the coil to catch the liquid as it defrosts. Afterwards, you can try restarting the system, but if the coil freezes again, you’ll need an expert diagnosis.
• Blower unit. If the blower fan motor seizes up but is still receiving power, it can produce a distinctive buzzing noise.
• Outdoor compressor/condenser. A loud humming originating in your outdoor unit might be caused by a failed contactor relay switch, in which case the unit won’t start up. Or, a technician might discover that the fan motor has failed and needs replacement.
• Electrical components. Loose electrical connections or wiring anywhere within the system that produces a buzzing sound is a sign of arcing. When this occurs, there’s a risk of fire, so the situation needs prompt investigation.
• Breaker panel A loud buzzing coming from inside your home’s main electrical panel might be due to a faulty A/C breaker that’s being overloaded but won’t trip. This is a hazardous situation that needs immediate attention from a licensed pro.

If you have concerns about a humming air conditioner in your Peachtree City home, contact us right away at Powers Heating & Air.

Our goal is to help educate our customers in Peachtree City, Georgia and surrounding areas about energy and home comfort issues (specific to HVAC systems). For more information about other HVAC topics, download our free Home Comfort Guide or call us at 770-487-2040.