What could be wrong if your central air conditioner blows cool but not cold air and seems to be always running?

Answer 1

• Your condenser may be dirty and the evaporator coils should be cleaned there may be inadequate air flow around the condenser. if there is a leak, your unit may be out of refrigerant you might have a leak in your duct system[From The Home Energy Saver a webpage from the Berkeley Lab website.]
• You could have the same issue we have in our home currently. For some reason, the inside unit will run and run and it will get extremely hot in the house. Called out our service guy and the first thing he had found was that we had tripped the breaker for the outside unit (condenser I believe). Go with the cheap easy stuff first....
• I had the same problem and when the service tech came out it was determined that a faulty relay was to blame - the ac and heat were on at the same time! Hope this helps.
• Freon too low
• This answer is more often incorrect than not. Most new modern A/C units have a built in safety device to disable the compressor if the Freon is too low.
• Their could be a few answers to your problem. The condenser [ outside coil ] could be clogged causing a higher pressure witch means higher temp. it could be as easy as taking your garden hose and washing the coil, if the is packed you may need a power washer to clean the coil. You could also be low on refrigerant (Freon), which means you have a leak which needs to be repaired before you add refrigerant. Leak checking and adding Freon has to be done by a certified tech. You could wash the coil your self. Make sure the unit is off by the breaker to be safe.
• Never clean coils with power washer you will regret it condenser coil dirty evaporator coil dirty low on charge freezing up most of the time indoor coil the evaporator is not cleaned by service techs causing coil to freeze or being over charged clean is the key all coils not just the outside.
• We have had this happen to us twice now. My husband's uncle works in HVAC and suggested that the first things we do were A) check the cleanliness of the filter and B) turn OFF the air conditioner (I think he also suggested tripping the fuse for the unit) for about 10 minutes. Luckily, both times this has happened to us, this has fixed the problem. I don't know what causes it to stop cooling the air sufficiently but turning it off seemed to reset it somehow. I know this is not a true "fix" but it is a good first step before calling a repair man.