An air conditioning system fails mainly because of a bad compressor. After a couple of minutes you turn the air conditioner on, the compressor kick starts to dispense cool air. However, if the compressor is taking more than the expected time to start or is not starting at all, you have a bad compressor that needs to be repaired immediately to avoid further damage to the appliance.
Sometimes, the compressor could lose its refrigerant gas charge due to a fracture to the copper pipe or a leaking valve. This should be immediately brought into the attention of A.C expert, because a compressor running without adequate refrigerant gas depreciates in efficiency prematurely.