When an air conditioner operates normally, it should hardly make any noise. When it starts making loud noises, it’s not an indication that it’s possessed, but it can give you insight into what’s happening. Consider the following common noises an AC may make and what they may be telling you.
Banging, Clanking or Thumping
Some of the most noticeable noises are when the air conditioner makes loud banging, clanking, or thumping sounds. Banging sounds inside may indicate your ducts are contracting as they cool down with the cold air moving through them. Outside, it could indicate something in the compressor has broken.
Clanking and thumping sounds often relate to loose or broken parts. These are frequently at one of the fan motors or the compressor.
Buzzing
A loud buzzing sound may happen if your air conditioner coils freeze up. However, buzzing can also indicate a problem with the outside condensing fan motor or a compressor malfunction.
Squealing or Grinding
Squealing and grinding can be nerve-racking, especially if it gets loud. Your circulating and condensing fan motors have ball bearings that allow the spindle to spin the fan blade or wheel. However, these bearings need lubrication to keep from seizing up. Squealing and grinding often trace back to these bearings not having adequate lubrication and wearing out. If you hear grinding or squealing, turn off the air conditioner until you can get it looked at to reduce the risk of ruining the fan motor.
Hissing or Gurgling
The air conditioner relies on a pressurized refrigerant system. If there’s a hole or leak in the system, you may hear a loud hissing sound. These are usually very substantial leaks.
Refrigerant leaks may also cause a gurgling sound due to trapped air in the system. However, this can also be traced back to a clogged condensation drain, which is responsible for draining the moisture the AC condenses from the air.
Humming
Humming usually points to some electrical component problem. One of the key components that may emanate a humming sound is the condensing capacitor. This special electrical component stores a large electrical charge to help start the compressor and condenser fan. When the capacitor goes bad, it hums when the system is trying to start up. Fortunately, this component is relatively easy and inexpensive to replace. In some cases, a condenser fan motor that’s burning out may also produce a humming.
Rattling
Rattling typically comes back to two different sources. The easiest of the two is debris caught in the fan that’s rattling as the fan spins. Turn the unit off at the thermostat and the breaker before attempting to check or clear any debris caught in the unit.
Rattling can also be traced back to loose components. The air conditioner vibrates as it runs, which can loosen hardware and allow parts to rattle. Further, broken parts can also cause a rattling sound as the unit runs, especially inside the compressor.
Clicking or Chattering
An air conditioner will naturally click as it runs through a cooling cycle. You may hear this clicking at the thermostat, inside at the control board or outside at the condenser unit. However, these should be single clicks, not repeating throughout the cycle.
A rapid clicking sound indicates a problem with the contactor in the condenser unit. Some people say the sound reminds them of the windup chattering teeth toy. The contactor acts as a switch to allow the high-voltage current to pass through the circuit at the condenser unit. It receives a low-voltage signal from the thermostat, which closes the circuit, allowing the stronger current through. However, when there’s a problem with the contactor or the signal coming to it, it may cause the chattering sound.
Evaluating and Dealing With Sounds
One of the best ways to stay ahead of all of these sounds is through routine AC maintenance. The maintenance technician will check for unusual sounds and the possible cause of many potential sounds, including the refrigerant charge, and test individual components. They’ll also tighten the mounting hardware and electrical connections. If they find a component that needs replacing, you can tend to it before it causes more substantial problems. If you’re already dealing with loud and unusual sounds, you may need to schedule a repair visit.
Whenever property owners around Galveston need help keeping their homes comfortable, they turn to George’s Air Conditioning. Since 1999, our team has provided trusted heating and AC repair, maintenance and installation along with indoor air quality solutions and duct cleaning. Call to schedule a repair visit with one of our expert technicians to get to the bottom of the strange noises your air conditioner is making.
