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What Size Breaker Does a 30 Gallon Water Heater Need?

Water heaters are one of the most essential appliances in our day-to-day lives. Especially in the United States of America, water heaters are a lifesaver in states where the winters are bitterly cold all year.

In order to keep the water heaters working for a long time, it is critical to configure the amperage, voltage, power, and breakers appropriately.

Otherwise, incorrectly setting your electric water heater might result in substantial damage to your other appliances, as well as unintended mishaps.

Let us discuss the breaker size for a 30 gallon electric water heater, as well as the methods for determining the breaker size, the benefits and drawbacks of employing a big or small breaker, the use of amps and watts in a 30 gallon electric water heater, and much more.

What size breaker does a 30 gallon water heater need?

A 30-gallon water heater requires a 30 amp breaker. You can use a 30 amp double pole breaker to ensure its smooth functionality. You might also utilize a 25-amp breaker as well. However, a 30 amp breaker is strongly suggested since it can power any water heater, regardless of its gallon capacity.

As the water heater continuously consume power, you need to make sure to use the proper size breaker for continuous flow. And 30 amp breaker works fine for the issue.

Breaker size for 30 gallon electric water heater:

It is essential to choose the appropriate breaker for your water heater. Otherwise, the entire circuit might be tripped.

Each circuit breaker is used to manage the electrical demands of various equipment. Water heaters, too, require a separate breaker in order to work properly.

Considering amperage and voltage are two of the most crucial aspects of choosing the right breaker. Because amperage and voltage are interdependent, adjusting one will have a major impact on the other.

However, this may differ based on the type of water heater you have. A 30 amp double pole breaker is required for a 30-gallon water heater.

Water heaters rated at 4500 watts may be powered by 30 amp circuit breakers. It’s also worth noting that 30 amp breakers may be utilized for water heaters of any gallon size.

As a result, a 30-gallon water heater may easily be powered by a 30 amp double pole breaker. Because this 30 gallon water heater consumes roughly 3500-4500 watts, which a 30 amp breaker can easily manage.

Therefore, if you’re installing a new water heater in your home, a 30 amp circuit breaker may also be used for 30-gallon water heaters.

How to determine breaker size for a water heater?

There are a few things that you need to consider to get the proper size breaker for the water heater. Let’s get to know them.

Check for the wattage and voltage:

The first and foremost thing that you should do in order to determine the size of the breaker for a water heater is to find the wattage and voltage.

It will be clearly written in the manual of your water heater. Or, you can also find it near the thermostat panel of your water heater or at the base of it. So, note it down accordingly.

Divide the wattage by voltage:

After you are done finding the wattage and voltage, divide the wattage by the voltage. Be careful with the decimals and try to round it up as a whole number for easy calculation. Write the result accordingly in your notebook.

Multiply the result by 125%:

According to the National Electric Code (NEC), your breaker should be sized at 125% of the electric load rather than the actual electric load of the water heater. It is mainly done in order to maintain the safety protocols.

Therefore, multiply the figure obtained by dividing the wattage by the voltage by 125%. Lastly, to determine an estimate of the size of your breaker, round it up to the next whole number.

What happens if breaker is too big or too small for hot water heater?

Once you install the breaker for your water heater, it will maintain the power flow to it. But if it is not the proper size, then there might be issues in the future. Let’s get to know what happens when you don’t get the proper size breaker for your water heater.

The breaker will keep tripping:

If the breaker is too big or too small in size for your hot water heater, it will continuously keep tripping, disrupting the electrical connection of your water heater. This continuous tripping of the breaker might damage your water heater permanently.

Internal damage to your water heater:

Another issue with installing a breaker that is too big or too small for your hot water heater is that it might cause internal damage to the appliance.

Because a breaker that is too big or too small may cause serious problems with the water heater’s operation. Due to the incorrect breaker size, the amperage, wattage, voltage, and wiring would all be adversely affected.

The risk of untimely accidents:

The danger of premature accidents is the most significant risk associated with using the incorrect size of breaker. Even the simplest changes in size might result in fatal mishaps.

Other electric concerns, such as damage to other appliances, circuit failure, and power outages, will be a major headache just because of using the wrong size of breaker on your water heater. 

Furthermore, short circuits may result in fires, resulting in significant property damage.

How many watts is a 30 gallon water heater?

A 30 gallon water heater usually uses 3500 watts. However, this wattage might vary depending on the model that you are buying for yourself.

The capacity of wattage in a 30 gallon electric water heater can be anywhere from 3000 watts to 5000 watts.

Depending on the wattage, the amperage and the voltage would also vary significantly. Therefore, it is highly recommended that you check everything carefully while setting up your 30- gallon water heater.

How many amps does a 30 gallon water heater pull?

Typically, a 30 gallon water heater draws 18.75–18.80 amps. The National Electric Code (NEC) guidelines established this as the normal amperage range.

The size of your breaker should likewise be set at 125% of the load, according to the NEC standards. Water heaters use a substantial amount of energy. As a result, for safety purposes, the NEC has set this code.

If your 30 gallon water heater uses 4500 watts and is powered by 240 volts, the range of 18.75–18.8 amps applies.

But, as we just saw about the NEC code, this figure should be multiplied by 125% to keep the size of the breaker a bit more than the required amount.

Thus, it would be nearly 23.43 amps, which can be rounded up to 25 amps. For a 30 gallon hot water heater of 4500 watts and 220 volts, the amperage count would be nearly 30 amps considering the 125% of the load.

What size wire for 30 gallon electric water heater?

The size of the wire required for your 30 gallon water heater is determined by the amount of watts and voltage used. However, 10-2 Non-Metallic (NM) or Metal-Clad (MC) wires are typically required for a 30 gallon water heater.

If your 30 gallon electric water heater uses 4500 watts, then a 10-2 wire is required for its smooth functionality. On the other hand, if your 30 gallon electrical water heater uses 3500–3800 watts, then it requires a small wire of size 12–2.

You can also use 8 gauge wire for your 30 gallon electric water heater. The size of the wire will vary significantly as per the usage of power by your 30 gallon electric heater.

You can use both non-metallic (NM) and metal-clad (MC) wires for your 30 gallon electric water heater.

Does a 30 gallon hot water heater need its own breaker?

Yes, a 30 gallon hot water heater needs its own circuit. A water heater is a high-powered electrical appliance. As a result, it requires its own circuit breaker in order to function properly.

The situation is same in the case of a 30-gallon water heater. Because a 30-gallon water heater uses a significant amount of energy. It requires a separate breaker since it consumes more power than the other appliances in your home.

Furthermore, if you utilize the central breaker for your water heaters, a short circuit might occur, tripping the entire circuit and causing terrible unexpected accidents.

As each circuit breaker is used to manage the electrical demands of various equipment, a 30-gallon hot water heater also needs a separate breaker in order to work properly.

Final thoughts

A 30 amp double pole breaker is the best option for your 30-gallon water heater. Because it will not only ensure its perfect operation but also ensure that your water heater lasts for a long time. Therefore, be cautious while selecting the proper breaker size for your 30 gallon water heater.