Thermostat Keep Tripping Your Breaker? 6 Possible Fixes

Thermostat Keep Tripping Your Breaker

Does it seem like your thermostat keeps tripping your breaker?

Well, that could be the case, as there are a few reasons why that might happen. But I’ll let you in on something—chances are, your thermostat isn’t the problem at all.

Let me walk you through any issues that are directly related to your thermostat, and then address other, more common reasons for your HVAC to trip a breaker. Keep reading!

Misconceptions on Why Your Thermostat Is Tripping Your Breaker

If there’s an issue with the wiring to your thermostat, such as a short, this could be causing issues but NOT causing your breaker to trip.

Thermostats are typically on a low voltage 24v circuit, via a transformer in the furnace or air handler.

The wiring for the thermostat will only pop a low voltage fuse in the furnace or airhandler, it won’t be tripping your breaker.

So while this is often the first thing people think of – and it’s definitely worth checking for that blown fuse – wiring issues in your thermostat shouldn’t be what’s tripping your breaker.

Hands Measuring Conductivity Of AC
While there are some reasons why your thermostat may be responsible for tripping your breaker, most of them can come from other parts of your HVAC system.

Reasons Why Your HVAC Is Tripping Your Breaker

1. Problems with the Circuit Breaker

Yes, you may not need to look any further than the circuit breaker itself. Here are some common reasons for circuit breakers to trip.

Overloaded Circuits: There really shouldn’t be a problem with your furnace breaker as most building codes call for the furnace to be on a dedicated circuit. Additionally, air conditioners that are more than 15,000 BTUs should also be on a dedicated 220-volt circuit as well.

Short Circuits: If you have a short circuit somewhere in your wiring, it can cause the breaker to trip. This happens when a hot wire comes into contact with a ground wire or grounded component, resulting in dangerously high electrical currents which in turn trips the breaker.

Short circuits can originate anywhere in your wiring, so identifying the source can be difficult. However, one telltale sign of shortcircuits is a burnt odor or visibly scorched wires.

Finally, you may just have a bad circuit breaker but fortunately, that’s fairly easy to troubleshoot. Check out the video below to help you determine if you have a bad breaker.

2. Airflow Issues

Anything that causes your HVAC system to work harder can increase the amount of electrical current it’s pulling, which in turn can trip your breaker.

While many think that a dirty filter can cause this, it will actually cause a lower amount of airflow – which means your AC needs to do less work. Though this can cause the coils to freeze.

Instead, airflow issues to your outside condenser can cause amps to increase – which could cause a breaker to trip. The dirty condenser will cause pressures to increase and will increase the amps, until eventually you get a trip.

Any of the following will impact your system’s airflow and cause it to work harder.

Solution. Give your outside AC unit a quick check over. Access the condenser coils and remove any dirt or debris with a soft brush or even a light rinse with the garden hose.

3. AC Compressor is Hard Starting

The compressor is inside the outdoor unit that sits by your house and it moves refrigerant to the indoor evaporator coils—if you watched the video just above, you’ll be able to see how this works.

The compressor is the heart of your air conditioning and they wear and tear with age. At some point, they begin to struggle at start-up—it becomes more and more difficult for them to come on and stay on. This is called hard starting.

The problem is that hard starting causes a much bigger pull of power and it can cause your breaker to trip.

Solution. In many cases, trying to fix a hard start issue by yourself might cause bigger issues. You are better off calling a pro for this one.

Typically what’s happening is that a capacitor may be low and need replaced. The unit may also simply need a device called a hard starter, which is just like a strong kickstart.

5. Dirty Condenser Coils

Also part of the outdoor unit, if your condenser coils are dirty it makes your air conditioner work harder and could potentially trip your breaker.

Solution: Keep your coils clean! Check the video below for instructions.


If your HVAC is tripping a breaker there’s a good chance the reason has nothing to do with your thermostat. The fault likely lies with one of the reasons mentioned above.

To recap, check for the following issues.

  • Problems with the circuit breaker
  • Lack of airflow
  • Frozen evaporator coil
  • Ac compressor is hard starting
  • Dirty condenser coils

Having said that, it is a good idea to make sure the wiring to your thermostat is good!

Hopefully, this article has helped you source your problem.

While you’re here, why not check out the related posts below. Perhaps we can help you with something else.

Thanks for reading!

I've been helping homeowners with appliance repair since 2016. Starting out as an enthusiastic amateur, I've since worked with many Appliance, HVAC, and DIY experts over the last 7+ years. My mission is to help fix your appliances and prevent future issues - saving you stress, time, and money. Visit my author page to learn more! Read more