Central Air Conditioning Equipment Doesnít Work At All

If your central ac doesnít go on immediately when the thermostat signals the need for cooling, itís most probably that the thermostat isnít functioning properly or the unit is receiving electrical power. Before you do anything else, be sure the thermostat is set to COOL and its temperature setting is well below the ambient temperature.

Then do the following:



1 Test the primary electrical panel as well as any secondary circuit panels for a tripped breaker or blown fuse. If you find the problem there, reset the breaker by turning it off and then on or replace the fuse. A central air conditioner must be on a dedicated 240-volt circuit.



2 Ensure the air conditioner on / off switch is turned on and that the outdoor condenserís on / off switch, that is mounted on the outdoor unit, hasnít been shut off. Also be sure the 240-volt disconnect next to the compressor, which happens to be in a metal box usually installed on the house wall, hasnít been shut off.



3 Turn off the power to the ac and check the thermostat. Remove the thermostatís cover from the bottom (usually by yanking straight out) and replace the batteries (if it has batteries). Replace the cover and wait 3 or 4 minutes and try the system again.



4 If that doesnít do the job, open the thermostat again and unscrew the wire from the Y terminal. Turn the power back on. Holding the wire by its insulation only, touch the bare end to the R terminal and keep it there for approximately two minutes. If the compressor kicks on, the thermostat is bad; change it out. If the compressor doesnít go on when you hold the two wires together, switch the power back off and call up an air-conditioning professional.



Still not working? Please keep reading.



Air Conditioning Equipment Doesnít Cool Well



If you're able to hear your central ac running, but it doesnít cool well, the problem can be caused by a number of issues. The very first thing to do is make sure the filter in the air handler is clean so that it receives proper air flow.



1 Turn off the power to the air conditioner.



2 Remove the door on the front of the air-handler cabinet to give you accessibility to the filter. Pull out the filter and clean or replace it as needed.



3 Look for ice. If you see ice in the area around the coils, close the system back up, switch the power back on, and turn on the fan. The ice should melt within an hour or two.



4 Clear the condensate drain. Ac units can create a lot of water simply because they remove moisture from the air. To eliminate this, there is a [usually plastic] drain pipe that comes out of the side of the air handler. Over time, algae can block this water pipe and, when it does, the A/C wonít work. Water is also likely to puddle near the system or even flood the area. 



5 Clean the outdoor compressor. 



6 Make sure the compressor is operating. Whenever you set the thermostat to a temperature below the room temperature, you should hear the outdoor compressor run and see the fan turning inside the top. If the fan isnít turning, search for an overload button or switch to reset (not all types have this). Stick a screwdriver down through the top grille and try to spin the fan blades clockwise. They should spin freely. If doing this gives the fan enough of a boost to get going, the device has a defective capacitor that must be replaced by an Ac repair technician.



If none of these methods worked, the likelihood is pretty good that the coolant needs to be recharged by an air conditioning professional.



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