Why an Air Conditioner Can Trip the RV Breaker

It's not uncommon that the air conditioner in an RV trips the breaker. You've likely experienced it too since you're reading this article. So here's what to do if it happens!

person fiddling with rv circuit breaker

When you’re traveling and it’s hot, you just want your RV air conditioner to work. So when it starts to trip the breaker, and you are left with unreliable air conditioning, it can be quite frustrating. However, this isn’t an uncommon problem, and if you’re dealing with an RV air conditioner that keeps tripping the breaker, you’re not alone.

What do you do if your RV air conditioner keeps tripping the breaker? Well, first you need to figure out why this is happening, and then look for solutions. Many times the reason the AC is tripping the breaker is simple and relatively easy to resolve. Sometimes you may need to use the skills of a professional to fix your problem.

6 reasons why the breaker keeps tripping

man fixing an rv air conditioner on the roof

Before you run out and have the air conditioner in your RV replaced, you should do a little trouble shooting to figure out why the air conditioner is causing problems. Here are the 6 most common reasons:

  1. The air filter inside the AC is dirty
  2. The outside of your AC is dirty
  3. The circuit breaker is dead
  4. The AC motor has a short
  5. The compressor has trouble starting
  6. The compressor is grounded

Let's take a look at the reasons above and what to do if you experience them.

1. The air filter is dirty

important for keeping the air passing through your AC unit clean, when it’s cleaning the air, it’s holding on to all of that junk. Over time, if the air filter isn’t cleaned or replaced, that built up junk can cause reduced air flow through the air conditioner, causing the motor to work extra hard. This can cause the breaker to trip.

Solution: This seems like a bit simple to discuss, but you should replace or clean the filters on your RV air conditioner frequently, or at least once per year. Not only does this keep your AC unit running efficiently, but it will improve the air quality in your RV.

2. The outside of your AC is dirty

The exterior part of your RV air conditioner can build up dirt, dust, leaves, bugs and other stuff. This stuff gets wedged between the coils that are intended to cool hot air being passed over the coils. When these coils can’t work correctly because they are dirty, and the dirt is holding in the heat, your RV air conditioner will trip the breaker.

Solution: To solve this problem, you’ll want to carefully clean the fins and coils of the outside portion of the air conditioner unit. This can be done by using an air compressor to gently blow out any dirt and debris stuck on the fins. You can also use a soft brush or a gentle stream of water. You’ll want to be very careful with this process because bending or damaging the fins can cause the unit to work harder than necessary.

3. The circuit breaker is bad

The problem with your air conditioner tripping the breaker, may have nothing to do at all with the air conditioner. Sometimes breakers go bad, or the wiring to the breaker may be loose or corroded. If any of the issues are occurring with the breaker attached to your air conditioner, anytime you run the air conditioner, the breaker will likely trip.

Solution: Circuit breakers aren’t exempt from problems. If you suspect that the circuit breaker is the problem and not the air conditioner unit, there are a couple of things you can do. First check the breaker box and make sure that all of the wires to the breaker are connected tightly to the breaker. Then check the breaker. Circuit breakers do go bad, and you may simply need to replace the breaker.

4. The motor has a short

A short in your air conditioner motor is most likely caused by damage to one or more wires connecting the motor to the circuit breaker. Wires can become damaged due to time, general wear and tear, rodents or other conditions. When wires are damaged, the electrical current doesn’t follow the correct path. Shorting circuits will trip the breaker as a matter of safety.

Solution: Unfortunately, the only solution to this problem, in most cases, is replacing the motor. If your RV repair person or electrician can find the direct source of the short, they may be able to fix the problem, but shorts can damage the motor.

5. The compressor isn’t starting well

The compressor of your RV air conditioner is like the heart of your air conditioner. This part creates pressure within the coils, causing the gas inside to decrease in temperature and cool the air around it. If the compressor isn’t starting well, this can cause the air conditioner to trip the breaker.

Solution: If your AC unit is having a hard time starting and trips the breaker before it ever gets going, the capacitor may be bad. To fix this you can have your RV repair person install a “hard start kit”. This will give a boost to the capacitor. If that still doesn’t work, you’ll need to replace the capacitor.

6. The compressor is grounded

This is often called a “direct short” because the cause of the short is an exposed wire touching the casing of the compressor. If this is the problem with your RV air conditioner, you’re likely in for a pricey repair.

Solution: As with the motor, if your compressor is grounded, the only option you likely have to stop the air conditioner from tripping the breaker is to replace the compressor. This is actually the worst case scenario for your RV air conditioner. If your RV mechanic tells you that your compressor is grounded and should be replaced, you are probably better off just replacing the whole outer unit of the air conditioner. Compressors are expensive. In many cases a new outside unit may be the cheaper option.

Why should you reset your RV air conditioner?

Sometimes, before you start troubleshooting your RV air conditioner, you may want to try resetting your air conditioner. There are a couple of indicators that you can look for that may indicate that it’s time to reset the AC unit.

First, if the AC unit is not blowing cold air, even if the thermostat is set as low as possible. Second, if your RV experiences a power surge and overloads the circuit. This can cause the breaker to trip, and you’ll want to reset the AC unit. And last, if your AC unit has a grounded short, a short circuit or other issue that would trip the breaker. The sudden shut-off of the AC unit may confuse it, and make resetting the unit necessary.

How do you reset an RV air conditioner?

If you need to reset your RV air conditioner, and you’ve never done it before, it may seem like a scary or difficult task. However, the sound of the process is more daunting than the actual process. Most people can confidently reset their RV air conditioner without assistance from a mechanic. There are two ways to reset your RV air conditioner.

1. Reset with the AC unit reset button

Many newer AC units have a “reset” button to make the process of resetting your AC unit easier. Each make and model will likely have the reset button in a different location. Generally, this red colored button is located on the back of the AC unit, but sometimes they can be located inside of the panel. To reset your AC unit with the reset button:

  1. Turn off the power of the RV air conditioner.
  2. Depress the reset button and hold it down for three to five seconds.
  3. Release the button and wait for 10 to 15 seconds.
  4. Depress and hold down the reset button for another three seconds.
  5. Turn the power to the AC unit back on. This should reset the unit back to normal operating conditions.

It is important to keep in mind that this is a general procedure that works for most AC units with a reset button. However, before you proceed with resetting your AC unit, consult your owner’s manual for the procedure that is recommended by the air conditioner manufacturer.

2. Manually reset your RV air conditioner

Older air conditioner units on RVs may not have a reset button. And even some newer AC units don’t come with a reset button. If this is the case for your RV, you’ll need to reset the air conditioner, manually. This process isn’t difficult, but as with using the reset button, you should check with your owner’s manual for the recommended process for resetting your particular air conditioner unit.

  1. Turn off the air conditioner.
  2. Unplug the air conditioner from the outlet.
  3. Shut off the breaker that corresponds to the air conditioner unit. If the breaker for the air conditioner has tripped, this breaker will appear to be off, but it really isn’t. You’ll need to set the breaker switch all the way to the off position.
  4. Using a voltmeter, check the breaker to ensure that it isn’t the cause of your AC problems. If the breaker reads 120 volts or 140 volts, the breaker is fine. If it doesn’t read one of these voltages, the breaker needs to be replaced.
  5. Once you’ve confirmed that the breaker isn’t the problem with your air conditioner, wait an additional 60 seconds to turn the breaker back on.
  6. After 30 minutes you can plug the air conditioner back in and turn back on. Waiting allows the thermostat to return to normal operating conditions.

One final comment about safely operating your RV air conditioner. If the air conditioner causes the breaker to trip even after it’s been reset, and you’ve done the “repair” steps that you are able (replace the filter, clean the outside unit, or replace the breaker), do not keep resetting the breaker, and letting it trip repeatedly.

This can damage your RV’s electrical system and could potentially lead to a fire. When in doubt, have a professional troubleshoot your RV air conditioner problems.