Why Is Your AC Unit Making A Humming Sound?

Why Is Your AC Unit Making A Humming Sound?

Why is your AC unit making a humming sound?

A humming sound inside your air conditioner is an indication that it needs repair. Your entire HVAC system communicates with one another. Your air conditioner requires adequate airflow to function efficiently.

The air filter allows air to pass through, and the blower motor in the furnace moves air throughout the entire system to heat or cool your home. It can cause issues with your condenser unit outside if the air filter is dirty or the blower motor fails.

Hire an expert AC contractor in Mesa, AZ, to provide unmatched air conditioning repair, installation, and tune-up services.

Causes of a humming sound from AC unit:

Condenser Fan Motor

In this case, the condenser fan motor could not spin but is still connected to power, causing resistance that results in a pronounced and often loud-humming sound.

Relay Switch

The relay switch is responsible for starting the outdoor unit when the indoor temperature reaches the required cooling level. It may be malfunctioning mechanically or electrically.
It is possible to hear a humming sound when the contractor malfunctions. You can find the switch outside your home in the condenser unit.


It is overloaded; normally, your circuit breaker trips if it becomes overloaded. If the faulty circuit breaker cannot shut off, you will hear an electrical humming sound.

Ice on the condenser

If your unit freezes up, you will hear a loud buzzing or humming sound. A frozen air conditioner may also be caused by a refrigerant leak, a clogged air filter, or a damaged blower motor. Often, a broken blower motor creates a buzzing or humming sound and is located in your furnace.
Your furnace may be mistaken for the humming noise source if installed close to the condenser. Find out whether the humming or buzzing is louder near the condenser unit or the furnace when the AC is running.

Broken motor

As with a broken blower motor, a broken condenser fan motor can also cause a humming noise when it malfunctions. If your indoor blower is running, but the fan is not turning, your fan motor may emit a loud buzz.
Some perceive this sound as more of a hum than a buzz. Failure of this component can be caused by debris rattling against the condenser, overgrowth near the unit, loose parts, etc.

Loose components

There are many moving parts in your HVAC system, so loose components can lead to problems. Due to normal wear and tear, parts get loose over time. A loose part may result in premature wear and loud sounds, such as humming. Get in touch with a professional for air conditioning repair in Mesa, AZ.

Installation services

Your air conditioner doesn’t need to be replaced because it makes a humming sound inside. When we handle your HVAC repair needs or air conditioning installation in Mesa, AZ, you can rest assured you’re getting the best value for your money.

Velocity Mechanical LLC can help you with HVAC services like installations, repairs, replacements, and maintenance. We provide skilled technicians for all your HVAC needs.