Wait don’t panic. There are a couple of things that can be simple fixes. First check the breaker. If it is tripped, do not reset it but call a technician. Tripped breakers can explode if there is a serious reason the breaker is tripped. Get a trained expert to find out why it is tripped before resetting the breaker.

Now listen to the cabinet that holds the controls. If you hear a humming sound, that indicates the unit is trying to come on but the high voltage is not getting through. This could be a capacitor, a wiring issue, or a motor issue. Check to see if the fan motor body is hot. If that is the case, then you may have a motor problem. Are the coils hot? This indicates the compressor is running but the fan is not.

Other issues may include low refrigerant levels triggering a low pressure switch. These are found on heat pumps and high end air conditioners as protection for the compressor. If you didn’t hear any humming, this could be the culprit.