How to Troubleshoot Central Air Conditoning
- 1). Ensure you have power by turning the fan to "on." If it doesn't come on, check the breaker box to see if it tripped. If it did, flip the switch back to on. If it didn't, call a repairman.
- 2). Check to see if any air vents are closed if you hear the fan running but no air is coming out. Without proper air flow, a unit can freeze up because the cold air backs up into the system. If you find any that are closed, open them.
- 3). Check air filters on the intake vent to see if they are dirty. Dirty filters can prevent warm air from being pulled into the system. A lack of warm air will also cause the system to freeze. If they are dirty, go to a local hardware store and purchase replacements. Put the new ones in place.
- 4). Turn the fan to the "on" position on the thermostat, instead of auto, and raise the temperature so that the system will stop trying to cool the house. This will allow only the fan to run. It will pull warm air into the system, which will in turn thaw the unit.
- 5). Lower the thermostat back down to where the air will turn on and turn the fan back to "auto." If cool air starts to flow through the vents, then your issue was air flow. If not, then check the duct work to see if any have come loose or have a hole. You will need the fan blowing for this so you can feel for air rushing out.
- 6). Call a repairman. If thawing the unit, after fixing air flow issues doesn't work, and there are no duct work problems, you will need professional help. You will also need a repairman if the problem is that the fan itself isn't working.
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