Air Conditioner Breaker Trips

I’ve been on several service calls where the problem was a tripped breaker. Of course, this causes the air conditioner to not function properly. Sometimes the problem with the air conditioner breaker trips is simple. However other times they are complex and result in a major repair. Here we’ll describe the two separate line voltage circuits for your split system air conditioner.  We will also describe the possible causes that will make your air conditioner trip the breaker. If you have a package unit then you will have a single circuit for your air conditioner. A package unit is an air conditioner or heat pump in one package (all in one air conditioner).

Working on any appliance including high voltage appliances is dangerous and should only be done by trained professionals. HVAC Systems use high voltage and all associated components including the breaker panel use high voltage. Always be safe and call a professional.

Air Conditioner Breaker Trips - The Circuits

air conditioner breaker tripsWith a split system air conditioner, you will have two separate breakers. One will be for the air handler and the other will be for the condensing unit. Depending on which breaker trips will depend on the problem. However, it is very rare for both to trip at the same time. That is unless you have a lightning storm or there is a power problem. Problems such as a brownout or malfunctioning transformer. That is a problem that your power company will have to resolve and not you or an HVAC contractor.

The photo shows an open breaker panel. It is not recommended that you open the electrical panel unless you have had specific training. Training in electrical safety and an understanding of the panel and wiring. It is possible the problem is in the panel by way of a bad or loose breaker. An HVAC technician can troubleshooting and quickly find the problem with the air conditioner breaker trips.

The breaker panel should be labeled for the appropriate appliance but sometimes it is not labeled properly. It is actually in the electrical code for the panels to be labeled for the location/circuit/appliance for safety reasons. However, they often not labeled or mislabeled. If your panel is not labeled properly or mislabeled you may want to call an electrician. They can perform this task for safety reasons. They should be able to provide you with a circuit map when they are done.

Never reset the breaker more than a few times. When a breaker trips continuously it means you have a serious problem that needs to be addressed before the breaker is reset.

Air Conditioner Breaker Trips - Causes with Explanations

Some of these cases described will require a professional to troubleshoot the problem while other cases described can easily be done by a homeowner. When in doubt or where safety is concerned, call a professional.

  • troubleshooting HVAC capacitors air conditioner breaker trips

    A bad dual-run capacitor. The top of the capacitor is all swelled up rather than being flat.

    Poor maintenance can cause air conditioner breaker trips. Dirty condenser coils will cause the air conditioner to draw more power. With this increased power use the heat increases. This will cause the air conditioner breaker trip if it is not rectified. Dirty clogged filters can also cause the breaker to trip. Make sure you do proper maintenance on your air conditioner. This will save you money on power usage and keep your unit reliable.

  • Bad breaker or power problem as described above.
  • A dead short where two wires are touching that should not be touching. It could also be a wire touching some metal and going to ground. Motors can have a short to ground and that includes the compressor. The compressor is powered by an electric motor and it can go bad or fail for various reasons.
  • Weak or blown capacitors can cause air conditioner breaker trips. Capacitors have two separate categories. One is a run capacitor which is common for all motors including the compressor. The other is a start capacitor which is only used on the compressor if your compressor is equipped with this component. HVAC capacitors go bad and cause breaker trips in your air conditioning system. *Three-phase and shaded-pole do not use capacitors. ECM motors do not use the type of capacitors we are talking about here. If you have an ECM blower motor or ECM condenser fan motor the capacitors are typically built into the circuit board or control module. In which case, you need to replace the board. In those cases, it is best to call a professional for repair.

Air Conditioner Breaker Trips - Causes with Explanations

    • A mechanical problem such as a bad bearing or something stuck that prevents or slows the motor from turning. The motor will work hard to run against that resistance. This will cause a high amp draw. It creates more heat and eventually, the breaker in your air conditioning system will trip. Most bearings for residential motors are non-serviceable meaning they do not require oil or maintenance aside from a periodic cleaning of the outer casing. Compressors for residential systems are hermetically sealed so there is no way to check a bearing or other mechanical problem. The problem needs to be looked at by an HVAC technician to be resolved.
    • Loose electrical connections will cause air conditioner breaker trips. This can be loose wires in any part of the air conditioner system. In my experience, I have found loose wires on compressors. The system was not properly maintained and the wires corroded eventually causing a loose connection. Many HVAC supply houses sell wires specifically to replace the leads on the compressor. These leads ensure a tight fit of the wires to prevent future problems with the wire leads on the compressor.
    • Short cycling of the system. This problem has become less of a concern since many people have modern digital thermostats. Modern digital thermostats have delay timers in them to prevent short cycling of the equipment. Short cycling is turning a motor off and then on again in quick succession. An electric motor goes from a dead stop to running at 100% in a split second. In that split second, while the motor is starting, it draws a lot of amps to overcome resistance. Short cycling a motor will cause more heat from the amp draw. It can cause the air conditioner breaker to trip. In addition to digital thermostats being used to prevent short-cycling, many manufacturers are adding this feature to their circuitry to prevent short-cycling problems.
    • Improper wire size will cause air conditioner breaker trips.

    Professional Troubleshooting for Air Conditioner Breaker Trips

Moreover, once again, most of the things listed will require the attention of a trained HVAC technician to troubleshoot and repair. If the system is newly installed and these problems occur then you likely have a problem with the installation. In that case, you need to call the installing contractor and have them fix it free of charge. Most installation contractors offer a 1-year warranty for workmanship. If they made a mistake, and it does happen, then they should make the repair for no charge.

Air Conditioner Breaker Trips - The Safety Codes

Furthermore, much of the things discussed in the article are covered under the National Electrical Code (NEC) or the Mechanical Code.  When an air conditioner or heat pump is installed it should have been inspected by the local municipality. These inspections check to ensure the system was installed according to all safety standards. The safety standards listed in the NEC and the Mechanical Code. This ensures the wire is sized properly for the ampacity ratings on the equipment and appliances.

Most HVAC contractors will get a permit and have these inspections done. It is not only their professional obligation required by law, it is also the safest thing to do. This all goes hand in hand with a proper installation. After all, if you do the job right you will have nothing to hide. Especially for an inspector to inspect the installation. Furthermore, quality installation is important. Having an inspector check to make sure safety codes are followed will add to that quality installation. Additionally, it can possibly prevent future problems such as breaker trips.

High Performance HVAC Heating Cooling
Air Conditioner Breaker Trips

To learn more about heating systems and HVAC use this resource.

See the About the Author page for information about the author of this article.

Share your HVAC Photos or ask a question about your HVAC System by uploading a photo of it.

Photo Uploads
Enter your name so we can credit you
If you have a website enter your website URL for additional credit
If you want to include a description then do so here.
Drop a file here or click to upload Choose File
Maximum upload size: 33.55MB
jpe, jpeg, jpg, gif, png, bmp, docx, doc, txt and PDF files allowed to be uploaded. Limit 15 files total and 100 mb/s max size.