June 14, 2019

Troubleshooting Your Air Conditioner


Troubleshooting your air conditioner system begins with a few common sense checks. If your air conditioning does not seem to be working, there are several things to rule out before you have to contact a professional. Checking these things first can save you a lot of aggravation and possibly money as well.


Checking your thermostat first is the best place to start troubleshooting your Air Conditioner not working. The three things to check here would be:

  1. Is there power to your thermostat. If it is powered by battery, you may need to change the battery.
  2. Make sure your thermostat is set to “Cool” mode.
  3. Be sure the temperature selection is set below the current room temperature.

Air Filter(s)

Dirty/Clean Air Filter

Your air filters can become clogged and restrict the air flow which can cause the unit to shut off. Make sure your air filters are clean. They need to be changed usually every three months or every month if you have pets or high traffic.

It does not take much debris to clog them and affect air flow, so if in doubt, change them.

Shut Off Switch

Many units will have a master shut off switch. Make sure that if your system has a shut off switch that it is turned on.

Circuit Breaker

For further troubleshooting, next look at your home’s circuit breakers to make sure that none of the breakers is tripped. If you do need reset the breaker, do it only once. A circuit breaker can be tripped and still look like it is on. Therefore, it is wise to just reset it anyway to be sure. Locate the circuit breaker to your air conditioning unit and turn it off, then click it back on.

Drain Pan

AC Drain Pan and Pipes

Check the drain pan under your indoor air conditioning unit. If it is full, then empty it. A full drain pan can trigger a float switch which can keep your system from coming on. If the drain pan is full, then it is likely that your drain pipes are clogged. The drain pipes will also need to be cleaned out or blown out so that the water can be evacuated before it accumulates.

What Next?

Once these troubleshooting steps have been checked and your system is still not working, it is time to call your air conditioning specialist. There are many components that if they fail can cause your system to not operate. Any of these issues should only be addressed by a licensed professional or damage can occur. Also a warranty can be voided and there can be costly and potentially dangerous hazards.

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