Outside AC Unit Not Turning On

Why Your Outside Air Conditioner Unit Is Not Turning On

Especially in the summer months, you rely on your outside air conditioner to cool your home and make sure your family is comfortable. But what do you do when the outside AC is not turning on? Before you call a professional repair service, check out these handy troubleshooting tips for some information that may help you diagnose the issue yourself.

Check the Thermostat or Temperature Control

The thermostat controls the air temperature inside your home. Check the controls right away to see if it is set to cool and also below the interior temperature, which should cause the outside unit to turn on. You may have to check the sensor bulb to make sure it's functioning properly, and for cracks or damage, and to ensure it is properly placed within the evaporator coil.

Problem with the Control Board

One potential problem if the compressor or fan does not turn on could be a defective control board, or PCB which many modern outside AC units have. Some of these control boards run on an internal fuse, so be sure to check for a blown fuse.

Change the AC Air Filter

If your air conditioner's air filter is clogged with dust and particles, this could cause the airflow into your system to become blocked. This in turn could result in overheating and automatic shut off of your AC. Always check the air filter to wipe off the dust and debris

Check the Emergency Shut-Off

Most outside air conditioner units feature an outside shut off switch so the power can be cut off in case of an emergency. Check that the switch is in the on position

Possible Tripped Circuit Breaker or Blown Fuse

Take a look at your home's electrical panel to check if the circuit breaker is tripped, or if you have a blown fuse. After you reset the breaker, if the unit still does not come on, you may have to consult a repair professional.

Clog in the Condensation Drain Line

The condensation line helps drain the condensed liquid out of your home. But when the humidity is very high, this line can become clogged, which in turn activates a safety shut-off switch. If you don't already have a condensation drain pump, try using a wet/dry vacuum to clean the blockage and clear the line.

Faulty or Unplugged Power Cord

If your outside AC unit is not turning on, it may be as simple as the power cord being unplugged. The cord can also be frayed or cracked, which could limit the power to the unit. It could also be improper voltage that's causing the power issues.

Air Conditioner Needs to be Reset

If all else checks out, you may need to reset your air conditioner unit. Try pushing the reset button, or if your unit does not have one, turn off the AC using the thermostat, wait 5 minutes, then turn it on again.