ac making humming noise inside houseNoisy air conditioners are a problem. A well-functioning unit should run quietly, but if your AC is making a humming noise inside the house, there are a number of things that could have gone wrong, which require your immediate attention.

Loose Parts

Loose parts are the most common reason your AC is making a humming noise inside your house. Though they operate on simple principles, air conditioners are complex machines. If something comes loose, the unit might not fail, but it may increase the strain on other components, wearing them down prematurely, which you can hear when you switch the unit on.

Poor Lubrication

Without lubrication, motor parts grind together. In the early stages, this will sound like humming but will grow steadily worse unless action is taken. Eventually, the motor may seize up and have to be replaced. Fortunately, with regular maintenance, AC motors can function quietly for years without any problems.

Contactor Failure

The contactor relay switch controls the flow of electricity into your air conditioner. It automatically disconnects the power once the unit’s done lowering temperatures in your home. When temperatures rise, it reconnects and powers the unit.

However, if the switch malfunctions, the unit won’t activate even if electricity is flowing into it. When this happens, the hum of the AC will grow steadily louder over time until it’s audible throughout your house.

Condenser Fan Motor

The condenser fan transfers heat from the condenser coils into the air outside. If the blades are stuck but the compressor motor is still working, the resistance can create a humming sound. Condenser fans jam for many reasons, such as loose parts or debris.

Ice in or on the Unit

It’s not uncommon for evaporator coils to freeze over. The most likely causes are refrigerant leaks, a clogged air filter, or a broken motor blower, which circulates cool air through your home.

Evaporator coils are delicate, so scraping off the ice isn’t a solution. In fact, it will probably damage the unit. Shut it off and let the unit thaw instead. That may solve the problem. However, if it reoccurs, you’ll need to call a professional.

Damaged Isolation Foot

The compressor is the noisiest part of your AC system. As low-pressure gas from the evaporator moves into the compressor, it gets converted into high-pressure liquid to expel heat and cool your home. Because this process causes a lot of vibrations, compressors are generally mounted on a rubber pad, called an isolation foot. If the rubber cracks or deteriorates, these vibrations can become audible, which is why your AC is making a humming noise inside your house.

Overloaded Circuit Breaker

Circuit breakers protect your air conditioner’s wiring and electrical components. They trip whenever the unit begins to draw excess power. However, if the circuit breaker is damaged, it won’t be able to cut power even when it’s overloaded. The buildup of electricity creates a humming sound and may pose a danger to the unit itself.

Vibrating Refrigerant Lines

When refrigerant lines are undercharged, the suction and discharge pressures inside are too low, which causes them to rattle. Replenishing the unit should fix the problem.

Who to Call When Your AC Is Making a Humming Noise Inside Your House

Regardless of the cause, humming is a sign your AC is suffering from a serious malfunction. For ordinary homeowners, repairing a faulty air conditioner is both costly and time-consuming. They have to locate a qualified repairman, pay for him to come out, and cover the costs of replacement parts.

However, for Homesential customers, the process is simple. Because we maintain an extensive network of HVAC technicians, support is always close at hand. Our help center operates 24 hours a day. Once you report the problem, we schedule an appointment with a local technician who will diagnose and repair your AC system. There’s no service fee. We cover the cost of parts and labor. Homeowners don’t have to lift a finger or open a wallet.

Homesential protects your home’s vital systems: heating, cooling, and wiring. Our plans are not only affordable, but bundling protection reduces your monthly premiums even further. Sign up today and protect your home and finances from exorbitant repairs!