Wouldn’t it be nice if we had air conditioners that could self-diagnose malfunctions and report them back to the homeowner, in detail? We’re sure that will exist someday, but in the meantime, we have to rely on other methods for an air conditioner to send warnings that something is wrong. Perhaps it’s a drop in cooling power, an unexplained spike in energy bills, or frequently tripping circuit breakers.
Or it could be something else entirely–strange and unfamiliar noises coming from the air conditioning system. Anything that’s different from the normal hum of the fans and compressors, and the occasional clicking as the system comes on and shuts down, might be telling you of a malfunction. Do not try to investigate these problems on your own, since there are various possible causes for them, and we don’t want you to injure yourself or damage the air conditioner even more by inspecting.
Be sure to call our HVAC pros and we’ll track down the exact source of the problem so it can be quickly repaired.
What Do These Strange AC Noises Mean?
There are a few common noises that indicate issues with an air conditioner:
- Shrieking: Do you hear a loud, mechanical shrieking noise? This can be the sign of a motor problem or at least a problem with a motor bearing that is wearing down. A worn-down motor bearing could eventually create too much stress for the motor and permanently damage it. Technicians can replace the bearings in order to rescue the motor.
- Grinding: This is another potential warning sign of motor problems–usually because of a motor with too much dust or too little lubrication. Additionally, if you smell an acrid scent from the vents, the motor is overheating. Shut off your AC and get a professional on the job ASAP.
- Rattling: This might be a minor problem, such as a loose cabinet door. Alternatively, it could be loose components being knocked around in the blower fan, bent fan blades, or a cabinet coming loose from the slab. If this noise seems to be coming from the ducts, there might be ductwork sections that have become loose.
- Hissing: One of the biggest hazards for an air conditioner is leaking refrigerant. This can occur for a number of reasons, but one common reason is corrosion on the refrigerant line. An early indication that this is happening is a hissing sound as the high-pressure gas escapes from the refrigerant lines. You’ll want to take care of this as soon as possible–technicians must seal the leaks and recharge the refrigerant back to factory levels.
- Clicking: You’ll hear clicks at times when the system starts up and cycles down. However, if you hear it too often when the AC is starting up, then you might have a “hard starting” air conditioner that’s struggling at powering the compressor. You’ll want to get this fixed right away.
- Clanging: A loud, and probably alarming, clanging sound could be a loose fan belt or a bent air handler that the fan blades are knocking into. These are most likely to occur in an older air conditioner. But if you hear it in a newer system, it’s definitely a good idea to call a pro!