Noises in the AC

If you can sometimes heat unnatural noises coming from your AC system then you may have a problem. These noises could be squealing, grinding or buzzing sounds. Most modern units have direct-drive motors although some older units are belt driven. Squealing sounds can occur when the belt is slipping. This is a simple repair of replacing a worn belt. If you have a squealing sound coming from a direct-driven motor then the problem is somewhat worse as the bearings are most probably shot. You should call in a HVAC professional to replace the motor. Buzzing sounds coming from your AC system usually mean a problem when the thermostat is turned on caused by the fan relay or the fan in the air handler. Switch the thermostat from HEAT or COOL to OFF. Then change the setting on the fan switch from AUTO to ON. The fan only should switch on. If at this point the air handler is making a buzzing noise then you probably have a faulty fan relay or blower fan.

A Noisy Outdoor AC Compressor

There are a number of noises you may hear from your outdoor compressor from buzzing to humming or even grinding. If you can hear a buzzing noise that sounds like the compressor wants to switch on but won’t start then the problem may be with the run capacitor. If the run capacitor is not operating correctly then the motor can get overheated when it fails to start. A thermal overload switch then switches the motor off. You probably need a professional in to replace the faulty part. Another indicator of a faulty run capacitor is when a humming sound is omitted when the thermostat is set to COOL. Again this will need to be accessed by a professional. If you are hearing a grinding sound from the AC compressor this is probably caused by the bearings in the motor being worn out. You will need to replace the motor.

Noisy Ductwork

Most heating and cooling ducts are made of metal and conduct a low level of noise from the AC unit into your living or working space. You can buy or ask your installer to insert flexible insulation ductwork to eliminate this sound. If your ductwork is emitting a pinging or popping sound it could be caused by a loose flap of metal. Making this more rigid will easily eradicate that annoying sound. If you are experiencing a rattling sound the cover panels are probably not as secure as they could be, by simply tightening them with a screwdriver should make this problem go away.

The AC Unit won’t switch off

If you are experiencing problems such the AC unit not switching off when the set temperature is reached then it is usually a faulty thermostat or a fault in the electrical system running the outside condenser. A temporary solution is to use the circuit breaker to shut of the unit but you should seek the help of a professional. If the thermostat reading is blank or if it shuts off when set to HEAT then you probably need a replacement thermostat. Other problems related to this could be wires fused together through continual use of relays or a wire has become disconnected. You could also try cleaning the condensing unit. Dirty coils in the condenser won’t give off efficient heat and this can keep the unit running.

Conclusion

The issues covered in this article are just some of the simpler problems that may occur that with a little regular maintenance on your AC system can often be avoided. You should always seek the guidance of a professional when repairs to your AC system are required.