If you go to turn on your central air and find that it won't turn on, then you want to figure out the problem as soon as possible, so you know whether you can take care of it on your own or have to put a quick call out to an HVAC company to get a tech out to fix it. A few reasons why your central air may not turn on can include:
A tripped fuse: This would be the easiest issue and one easily taken care of with the flip of a switch.
Check the switch – If a switch in the box isn't aligned with the others, flip it to off and then on.
Check the fuse in the control panel – Many models have a small fuse in the actual panel. Pull off the cover and see if the fuse has blown.
Replace the fuse – If this is the problem, replace that fuse with a new one.
Try the unit - Go back in the house and try the air again. If this was the problem then it should work as it normally does.
Caution: If you fix one of the problems and it happens again shortly after, have a tech come out anyway. Your unit may be pulling too much power which can cause major problems.
The AC may be frozen: Sometimes the coils freeze, stopping the unit from working.
Turn the unit to 'fan' – Turn the thermostat from cool to fan if you suspect this may be causing your issue. This will start the thawing process to take place.
Give it some time – Wait a few hours with the unit blowing on fan only before you try to turn on the AC again. This should be enough time to give the system time to thaw.
The motor may be out: It can happen where the motor of the HVAC system goes out. This is the worst case scenario because it means full system replacement. Unless, there is the off chance that a tech finds there is another problem within the motor that can actually be fixed by replacing a simple part.
Call out a tech – if this is the problem, a tech is the one you need, so make an appointment for one to come investigate the issue. You want to make sure you get a quote from them and get it fixed as soon as you can so you don't end up suffering too long. For more information, talk to a company like Green Air Inc.