When I turn my AC thermostat to cool, I can hear it click but the outside unit does not start and no air blows inside. Several hours later everything turns on and it works fine.

If it turns off, then it could be hours once again before it will start back up. For this reason I freeze my house before I let it go out again!

Any idea what may be causing this? I've had a capacitor go bad before, but the air was still blowing inside while the outside was humming. With this current issue, nothing seems to start.

Any ideas on what to look into is much appreciated!


This first thing to try is removing the thermostat and shorting the R and G wires. Usually, these are the red and green wires. This should start up the fan in the blower. If that works, try shorting R and Y (usually yellow). This should start up the fan in the blower, and the AC compressor. If all of this happens immediately upon shorting the wires together, then the thermostat is likely failed.

If shorting the wires as described does not immediately bring on the blower or compressor, the problem is probably either bad wiring or a bad relay or control board in your air handler.

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