Troubleshooting An AC Unit Not Working

If you think your air conditioner is not working

  • 1st check to make sure the thermostat is set to “Cool”
  • Check the main electrical panel and any secondary circuit panels for a tripped breaker or blown fuse.

If that is the case restart the breaker or replace

  • Check the thermostat is set to COOL. The temperature has to be 3 degrees below ambient room temperature.
  • Make sure the electricity is on. Check the switch in the furnace or air handler, and the outdoor condenser.
  • While the system is off, remove the thermostat’s cover, then remove the body from the base and replace the batteries.
  • ensure all wires securely attach to their terminals.
  • Replace the cover and wait 3 minutes, then restart the system.
  • If the AC system won’t start, check the compressor’s capacitor and wires, they could possibly be the cause.