If you’re like most homeowners, you don’t pay much attention to your air conditioning system until it stops functioning properly or begins to make strange noises. Sudden sounds coming from your system can be an indication that something is seriously wrong with the unit, but they can just as easily be caused by a nut or other small component coming loose and rattling around. Keep in mind, however, that it often requires a trained technician to make a definitive diagnosis, so don’t hesitate to contact our air conditioning repair service in San Diego, CA, if your AC suddenly starts making strange sounds.

Below are five common HVAC noises and their possible sources.

Buzzing Sounds

Buzzing sounds have a variety of potential causes. It could be that the blower unit is out of balance, the fan blades are loose or out of balance, or that the fan motor itself has come loose. It could also mean that the air filter needs to be replaced, so try replacing the filter first and see if the buzzing sound stops.

Clicking Sounds

Some degree of clicking sounds are normal in electrical components when an HVAC unit is powering up or down, but those occurring when the system is running could indicate a faulty thermostat or malfunctioning controls. It could also mean that a fan blade has come loose.

Banging and Clanking Sounds

These two sounds almost always indicate a broken, loose, or out-of-balance component. It could be a piston, the crankshaft, or possibly even the compressor itself. These sounds won’t go away on their own, and the situation will just get worse if you continue to run the unit, so shut it off and call for a technician.

Rattling Sounds

The first thing you should do after noticing a rattling sound coming from your HVAC system is to check for any loose parts. If you rule that out, check to ensure that no outdoor debris such as twigs or pebbles have found their way into your unit via the exterior compressor.

High-Pitched Hissing Sounds

For safety’s sake, shut your unit down immediately if it starts producing high-pitched hissing noises. This usually means serious issues with the compressor or the refrigerant, and allowing it to run could result in a serious and potentially dangerous breakdown.

Please feel free to contact us for more information on common AC noises or air conditioning installation, maintenance, and repair.