Water Heater Trips Breaker After a Few Minutes – Troubleshooting Guide

A tripped circuit breaker is not only frustrating but also, potentially, dangerous. 

A water heater will trip the breaker, in case there is an issue with the actual unit or the breaker, or if there is something wrong with the wires and connections. When it comes to the heater, a faulty thermostat, a burnt-out heating element, and a leak might be the problem.

Why Is My Water Heater Tripping the Breaker?

There are three main reasons that can cause the breaker to trip:

  1. The actual water heater – a bad thermostat, a burnt-out heating element, or a wiring problem might be to blame.
  2. A malfunctioning breaker – the breaker could have simply gone bad over the years or it is of the wrong size.
  3. A short circuit – the wires or the connections might have been damaged.

Read: What Type Of Water Heater Is Most Energy Efficient?

Water Heater Trips Breaker After a Few Minutes

The thing that might make your breaker trip in a couple of minutes is a leak that allows the water to come in contact with any of the electrical components.

A burnt heating element might also end up exposing wires and other electrical components to the water.

The combination of water and electricity will cause a short circuit and the breaker will get tripped.

Water Heater Trips Breaker Immediately

The most common reason for a tripping breaker is a malfunctioning thermostat. When the element is improperly installed or faulty, the thermostat won’t be able to ‘communicate’ with your water heater.

As a result, the element will fail to regulate the electric flow to the actual heating elements and will instead start feeding it into the circuit breaker. This excessive power will cause the breaker to trip.

Read: Why Is Water Heater Making A Loud Vibrating Noise?

Tankless Water Heater Tripping Breaker

If the actual breaker and the wiring are fine, then the chances are high that your tankless water heater has a faulty heating element that is tripping the breaker.

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Also, you would want to make sure that the breaker is the right size for the unit. Tankless water heaters, for example, require 40-50 amps for each wire.

Bear in mind that such units need quite a lot of electricity when they’re on (some – up to 30.000 watts).

Rinnai Tankless Water Heater Tripping Breaker

Pay attention to the code that would get displayed in case the water heater’s breaker gets tripped.

In a Rinnai unit, code 12 might appear. This means that there has been either a flame failure or poor ground.

  1. Verify that there is a fuel supply.
  2. Check the power supply.
  3. Make sure that the unit has proper electrical ground.
  4. Check the flue for any kind of obstructions.
  5. Check the gas valve and fan motor wiring as they might be defective.

Water Heater Breaker Tripped and Won’t Reset

Remember that the breaker trips for a reason. If you have tried solving the problem, but nothing seems to work, then you should call a professional as soon as possible.

Repeatedly flipping the breaker can damage it and even cause an electrical hazard.

Read: Why Gas Water Heater Keeps Cycling ON And OFF?

What Trips the Reset Button on a Hot Water Heater?

The water heater’s reset button is a safety device that will turn the power to the unit off when the temperature of the water inside the heater exceeds 180 F. The button can also be used to turn the heater back on after a power outage, for example.

Here are a few other things that can trip the reset button, except for the extremely high water temperature.

  • Loose wiring
  • A faulty thermostat
  • A grounding issue
  • A broken reset button
  • A worn-out heating element
  • Corrosion
  • A faulty breaker

Hot Water Heater Keeps Tripping Reset Button

  1. If one of the thermostats had failed, it might not turn the heating elements off, which will trigger the reset button. In such a case, replacing the element might be the best decision.
  2. A damaged heating element might have a crack in its metal casing or one of the wires exposed to the water. Such elements will not react to the thermostat’s commands and will continue heating the water, even when it’s not needed (this will trip the reset button).
  3. At times, the actual reset button is the problem. The element can get worn out over time, and it might start to cut the power off to the unit even when the temperature of the water is low.
  4. Electrical problems include a bad breaker (it can wear out) and loose wiring. A button that keeps tripping in such a case is actually fulfilling its main function and is trying to keep you safe.

Read: Why Is Gas Water Heater Humming?

Is There a Breaker on a Hot Water Heater?

Just like the reset button, a circuit breaker is a safety device. It monitors the circuit and if something goes wrong (there is an overload, for example), the breaker gets tripped and shuts off the power to the appliance.

Any water heater that has an electrical connection needs a breaker. The majority of gas-fired units nowadays require a circuit breaker as well, as they have certain elements powered by electricity. 

Where Is the Water Heater Breaker Located?

A water heater requires its own circuit breaker which is usually located in your home’s main electrical panel.

You’ll find this panel in the garage, utility area, or storage closet in most cases. To switch the electric power to the water heater or to reset the breaker after it had tripped, you would have to flip the breaker that is labeled ‘water heater’.

Water Heater Circuit Breaker Size

According to the National Electrical Code, the circuit breaker should always be sized at 125% of the load. In a nutshell, it would be better to invest in a breaker with a higher capacity that the electrical load on the water heater for safety reasons. 

The size of the circuit breaker is determined by the wattage of the unit and the voltage.

For example, a 4.500-watt water heater with 240 volts is going to need a 25-amp breaker.

To get that, you should divide 4.500 by 240, multiply it by 1.25 (the 125% that we have mentioned earlier), and simply round the number.

By the way, the circuit should be a dedicated one. This means that it should be powering only the water heater and no other appliances.

What Size Wire Do I Need for a 40-Gallon Electric Water Heater?

The breaker size cannot be determined by the size of the tank (the gallons). It is going to depend on the unit’s wattage.

Water Heater’s WattageBreaker Size (120 V)Breaker Size (240 V)
1.50015 amp15 amp
3.00030 amp15 amp
4.000N/A25 amp

Can I Use a 40 Amp Breaker for Water Heater?

The absolute majority of electric water heaters are going to need a circuit breaker that’s between 20 and 30 amps.

If you want to switch your breaker to a 40-amp one, make sure to change the wire as well. Most water heaters are wired with 10 gauge wire, while a 40-amp breaker is going to need 8 gauge wire.

What Happens If You Oversize a Breaker?

An oversized breaker will not trip when it is supposed to. 

The breakers that are too large are not as ‘sensitive’. It might not turn the appliance off if a wire starts burning.

All in all, an oversized breaker is definitely a safety concern.

Read: Gas Water Heater Not Maintaining Temperature

How Do You Know When a Breaker Goes Bad?

The most common signs of a faulty circuit breaker include:

  • A burning smell in the electrical panel – this means that the wires and insulation have overheated.
  • The breaker keeps tripping – there might be quite a few different things that will make your breaker trip; however, a faulty circuit breaker is one of them.
  • Physical damage – scorch marks and melted wires are tell-tale signs that the breaker is failing.
  • Old age – even though some breakers will serve you for decades (modern ones can last for up to 20 years), the older the element gets, the more likely that it will fail soon.

How Do I Test a Water Heater Circuit Breaker?

To test your water heater circuit breaker, you are going to need electric safety gloves and a digital multimeter.

Before removing the breaker panel and probing the element with the multimeter, you have to make sure that all the electronics close to the working area have been unplugged

If you don’t feel comfortable working with electricity, please do leave the task to a professional.