If your Air Conditioner has suddenly stopped working and won’t turn on, there are several things to check.
1. Make sure the thermostat is set to “Cool” and not been accidentally moved to “Off” or “Heat”.
2. Ensure the the thermostat temperature is set low enough to activate the AC unit.
3. Check that the external safety switch is set to the on position. This switch is usually located on an exterior wall near the condensing unit.
4. Check that the circuit breaker that controls the air conditioning compressor and the circuit breaker that controls the furnace blower or air handler, are in the “on†position. If a circuit breaker has tripped, reset the circuit breaker. If the circuit breaker cannot be reset, do not try to reset it again. Have a qualified technician check the unit to determine the cause of the problem.