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What Size Breaker Does a 40 Gallon Water Heater Need?

A breaker is an essential tool for any circuit that is dedicated to protecting any appliances in your household whenever there isn’t electricity overload. In today’s article, we will discuss what size breaker a 40 gallon water heater needs? 

What size breaker does a 40 gallon water heater need?

Generally, it is recommended to use 30A double pole breaker for a 40 gallon electric heater. You need to pair them using 10-2 nonmetallic cables. In addition to that, you need to have a 240-volt dedicated circuit along with the breaker and no other appliances should be connected to it.

Choosing the right type of breaker is important to prevent any type of accident such as an electrical overload or short circuit. In addition to that, the right circuit breaker will bring efficiency and convenience to your water heater.

When considering the breaker for your 40 gallon water heater, you need to keep into consideration a few factors. Voltage requirement is one of them.

Generally, an average voltage requirement for a water heater ranges from 220V to 240V based on the size of the water heater and used wattage. You need to place your 40 gallon water heater on a circuit depending on its voltage requirements.

Once you determine the required voltage for your water heater, you need to think about the wattage. Wattage varies on multiple factors that are closely related to your water heater such as the size, power, features, etc.

When establishing the connection between the water heater and the electrical connection of your house, you have to figure out the right type of wire that is compatible with the water heater.

So, it can ensure the proper flow of electricity to provide uninterrupted service to the appliance. Finally, keeping all these factors in consideration, you will be able to use the water heater in your house without any hassle.

Below is a brief discussion on the breaker size for your 40 gallon water heater:

Breaker size for 40 gallon electric water heater: 

Determining the size of the breaker for a 40 gallon water heater is important for an uninterrupted power supply to run the water heater in your house.

Using a 30A breaker is suitable for the water heater to bring maximum electric efficiency and safe operation to prevent any type of accidents.

Remember to determine the amp required for the heater. Then choose a breaker that is 125% of the size of the amperage. This is how you can easily figure out any breaker that is ideal for the water heater in your house. 

How to determine breaker size for water heater? 

It is always important to calculate the breaker size for the water heater to ensure uninterrupted electricity flow without damaging the wire.

In addition to that, a right-sized breaker will help to prevent any electrical load that can cause damage to the water heater. In some cases, your water heater may face an excessive power supply, also known as overload which can melt the wires.

This can lead to potential fire damage as well. That is why a circuit breaker will prevent the fire and keep it fine. When attaching a breaker to your water heater, you also need to have a 240-volt circuit along with the breaker.

This will provide safety and efficiency. In addition to that, no other appliances should be attached to the connection.

This will make it an ideal connection for the water heater.

Simply follow the tips to figure out and determine the breaker size for your water heater very easily:

Calculate the voltage:

It is important to calculate the voltage of your electric output to determine what size breaker you will need.

You can also have an idea of the average voltage requirements for the water heaters. Generally, most heaters require 240 volts power supply.

Find out the wattage:

Now, you need to know the wattage that your water heater requires to run. Generally, most water heaters run on 4500-watt power. This can also be considered as an average wattage for the water heaters.

Divide the total voltage by wattage:

Here is the calculation part. You need to divide the total voltage by wattage. So, if your water heater has a wattage value of 4500, and uses 240 volts power supply, divide 4500 by 240. 18.75 amps is the breaker size your heater requires.  

Why is breaker size important for hot water heater?

Wrong sized breaker can cause serious trouble in your house. If you have the right-sized breaker in your house, it will provide you with maximum efficiency.

It will also bring convenience to provide you with an uninterrupted power supply and run the water heater properly.

In addition to that, the right breaker helps to prevent any type of accident in your house If any electrical overload occurs, the breaker simply shuts off the appliance connected to it immediately.

That is why it is essential to protect the home appliances and make them work smoothly. A right-sized breaker will prevent electrical issues to cause damage to your appliances.

Below is a brief discussion on a few reasons why breaker size is important for water heater:

To protect the wire covering:

Sometimes due to heavy electric flow, your water heater wire cover can be melted. A circuit breaker will maintain the electric flow to keep the wire intact.

Maintain the electricity flow: 

Your appliances can face electrical issues such as aggravating, constantly tripping the breaker, and even overheating the wires which could lead to fire incidents as well. A breaker will prevent these issues.

Maintain performance and stability:

The circuit breaker can balance the electric flow to maintain the performance and stability of the water heater which will ensure maximum efficiency.

What causes the hot water heater breaker to trip?

Many reasons can cause the water heater breaker to trip. First of all, you need to determine the right-sized breaker for your water heater to make sure it doesn’t trip due to electric overload.

If you have installed the right size breaker for your water heater and it still tripping the breaker, it means some other problems are causing the breaker to trip frequently. Think flipping the Breakers repeatedly will solve the issue, you are wrong.

This could lead to damage to the breaker and melt the wires due to overheating. Below is a brief discussion on what causes the water heater breaker to trip: 

Faulty wiring: 

You can cause the breaker to trip frequently. If there are any loose connections between the wiring lines, or the wire itself is damaged, there’s a chance it is causing the breaker to trip. 

Thermostat issue: 

The water heater has two heating components, one on top and the other on the bottom which is meant to run one component at a time. If the thermostat goes bad it will cause both the components to run at a time and trip the breaker. 

Heating element issue: 

If the heating element of your water heater burns out, this cooler water comes out of the tap. And this could be a reason why the breaker is tripping.

Does a water heater need a separate breaker? 

It is recommended to provide the water heater with a separate breaker and circuit for maximum safety and efficiency. Generally, most electric water heaters require a 240 Volt circuit that is dedicated to running them.

When installing the circuit, you should also keep the cables into your consideration. In most cases, its 30-ampere double pole breaker requires a 240 Volt dedicated circuit and a 10-2 nonmetallic cable.

This is how you can ensure the proper safety and convenience for the water heaters in your home and prevent them from getting damaged due to any type of electric overload or short circuit issue.

What size wire do i need for a 40 gallon water heater?

Ensure proper electric flow for the 40 gallon water heater, choosing the right sized breaker is not the main thing. You will also look after the wiring.

Generally, most people recommend a 10/2 non-metallic cable for the water heaters that run on a 240 Volt circuit. In cases of water heaters, you need to remember that the larger the number of breakers, the smaller the wire.

In other words, you need to notice the thickness of wires because a 10-gauge wire is thicker than a 12-gauge wire. You should always match the size of the amperage with the wire to provide efficient electric flow.

So, it 10-gauge wire is recommended for a 25 amp to 30-amp breaker. A 40-amp breaker will usually require an 8-gauge wire.

Final Thoughts 

It is highly recommended to use a 30-amp breaker for the electric water heater in your house. You should always consider installing a 240 Volt circuit along with it. Use 10/2 nonmetallic or metal-clad cables to ensure maximum safety from fire or short circuits and keep the water heater safe.