Electric Water Heater Breaker Size – Comprehensive Break Down

You may be wondering which water heater circuit breaker will be the right size to have it installed. Some factors come in handy when picking a circuit breaker for your water heater, and they have to be considered for you to enjoy a continuous supply of hot water without fail.

One of the requirements before having your electric water heater replaced is a permit. The permit will allow the job to be inspected by a professional to ensure the replacement of your water heater will not interfere with the electrical or plumbing plans. It will be sure that the replacement of your water heater complies with area code requirements.

What Electric Size Water Heater Breaker is the Best?

This article will mainly focus on the electrical requirements that will be needed for a standard tank-style water heater. The need to replace your circuit breaker may be an upgrade from your previous one. You need to make sure all the electrical requirements and connections are up to date.

For your electric water heater to be of significant service to you, it needs a dedicated circuit breaker with 240- volts to serve the water heater alone.

The wiring is simple and straightforward whereby, there is a 30-amp double-pole circuit breaker plus a 10-2 non-metallic cable. The water heater circuit whereby the white wire in circuit is connected to the white wire lead in the water heater. The black wire is connected to the black wire lead in the water heater.EcoSmart ECO 11 Electric Tankless Water Heater, 13KW at 240 Volts with Patented Self Modulating Technology - Instant Hot Water Heater - Amazon.com

The white circuit wire is hot and not a neutral wire. You will have to mark it clearly at the ends of the water heater and the circuit breaker box. A 240-volt circuit, carries live current in both the black and white wires, unlike the 120-volt circuit.

This electrical connection is in a junction box that is at the top of your water tank heater. In the inspection of the connection in the junction box, you will need to uncover the plate at the top.

You will note that the wire conductors leading to your heater are enclosed always in a flexible metal cable. This flexibility makes it easier for you when replacing your heater, and it comes in handy in areas that suffer from earthquakes.

To test whether your circuit is working, have the cover plate removed and hold a non-contact voltage tester close to the wire connections. The tester will not light up if the circuit breaker has been switched off correctly.

Be sure to turn off the power connecting to the circuit before proceeding to touch or examine the water heater’s electrical connections.

The circuit enjoys a 30-amp double-pole circuit breaker. Have the appropriate circuit breaker in the breaker box switched off then proceed to use a voltage tester to ensure the circuit is off by testing the water heater.

The watts are labeled clearly on the specification in most of the heaters available in the market. The electrical wiring together with the circuit breaker will offer you the needed information to have your heater working correctly without tripping.

The present ground wire is in connection to the service ground with the other wire connected to the water heater ground connection.

A water heater with a 240-volt connection with a circuit breaker of 20-amp and a 30-amp in place is likely to start a fire with the latter likely to trip. The rating of the watts is clearly on the specification on the side of your water heater with a 216-volt water heater using more than 208 amps which is more than the circuit breaker rating.

To determine the size of the circuit breaker you will need for your heater you will need to multiply the value of your current by 125%. A circuit breaker of 156 amps will be of great help to a 1,500-watt heater with the 120-volt circuit. A 20 amp circuit breaker will be of great assistance to a 12 gauge wire.

Some years back, it was usual to have a 4000-watt water heater depending on a 20 amp circuit breaker. In the instance where your electric water heater provides you with cold water, there is a chance it may have tripped the circuit breaker. A large number of electric water heaters operate from 220 volts to 250 volts.

It is good to know about the inner wiring that leads to the heating element in your electric water heater. Each of the heating elements has a thermostat which can be found in the access panels that are mounted on the side of your water heater tank to control them.

The heating elements are connected with screws that lead to the water heater together with the thermostat. You will not need to interfere with this connection unless you have to replace the thermostat or the heating element in an existing water heater.A Must Read) Water Heater Breaker Size & Water Heater AMPS

Tripping your circuit breaker is something that can be avoided at all costs. All you need is to be keen on the circuit breaker you purchase for your heater. The calculations may be too much for an average individual, and you may require the help of an electrician with the installation of your circuit breaker.

With the right circuit breaker in place and the right conditions for your heater, you will be sure to have a constant supply of hot water at all times without fail. Be sure to follow the safety measures put in place before beginning your procedure to have your water heater circuit breaker replaced.

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How do I size a circuit breaker?

One thing we all need to know is that there are laws put in place that ensure the protocols, and the safety measures you need to follow to maintain your circuit breaker. Take note that your circuit breaker is larger by up to 125% compared to the circuit controls.

The difference comes in handy when there is an upsurge in temperature, which may be brought about by the continuous flow of current for more than three hours.

You need to be keen when purchasing the circuit breaker, the size that you will need to control the heater circuit by knowing the current rating of your heater.

You will not find the current rating on your heater specification when buying it, what will be of help to you is the power out of the heater plus the operation voltage. With the provided information, you will be good enough to come up with the current rating.

The specification of your heater will find it on the label of the box or next to the cord of the housing of your water heater. One thing you have to take note of is the power draw whereby it is in watts. Your heater for home purposes will be indicated up to 1,500-watts.

To get the maximum current flow, you will need the power specified on the label, and the operating voltage. The moment your water heater is plugged in, the voltage that is specified ought to be 120 volts, giving you a current draw of a 1,500-watts heater for 12.5 amps.

The size of the circuit breaker you will need for your heater is determined by the multiplication of the value of your current by 125%. A 15.6 amps circuit breaker will be of great use to a 1,500-watt heater on a 120-volt circuit. You will go for a circuit breaker with 20 amps since the 15 amp circuit breaker would not qualify as the perfect circuit breaker in size.

Be sure to include every device that draws current from the circuit when calculating the breaker size.
Something to note is that this calculation is similar to the heater operating at 240-volts circuits. They are on their power source due to the high demand for power.

What would cause tripping on my water heater breaker?

Tripping into the water heater may be experienced from time to time, and it should not deter you from having a water heater. The following are some of the reasons why your water heater would trip.

A faulty breaker
A defective circuit breaker will not stay put or reset when needed. You may have to replace a faulty circuit breaker to continue enjoying your water heater services.

A miniature breaker
Your circuit breaker expectation is for it to reset after some time, failure to which it may trip. An undersized circuit breaker will not be of service to you, and you will need to get the right circuit breaker in size for your heater.

Poor Wiring
The wires in your circuit will have your breaker tripping in the case where they are not correctly done. Your breaker will trip and may fail to reset.

Wrong connections
If the wires’ connection at the top of your water heater or the inside of your water heater if done wrongly, your circuit breaker is more than likely to trip from time to time.

Weak wires
The loose wires on your circuit breaker or anywhere in the circuit are likely to have your breaker reset after a while and then trip. The loose wires are known to be the main culprit for overheating.
A faulty part in the water heater

It will significantly attribute to shorting to the ground with the flow of electricity directed to the ground causing the wire to overheat.

Insecure breaker
A damaged busbar will have your breaker insecure or loose. The moment you get, and an electrical smell or a fizzing sound is when your circuit breaker is moved. You may opt to move your breaker to a different notch also wires to a different slot with the same size as the circuit breaker.

How do I measure my water heater’s breaker?

The purpose of the circuit breaker in your water heater is to regulate the current stream to your water heater. A circuit breaker is required for all your electric appliances and it is advisable to choose one with a high current rating will be advisable. It will allow the smooth flow of the current in the event that there is an increase in temperature.

The rise in temperature is not something new and will occur when there has been a continuous flow of current to a device for almost five hours continuously.

Before deciding on the perfect circuit breaker for your water heater you need to be sure of the working voltage of the water heater as well as the nominal current. The correct circuit breaker for your water heater will prevent your water heater from breaking down or tripping in any case.

You need to consider some factors when sizing a circuit breaker. They will be useful to you and your water heater in the long run. They include;

Your Heater Power Rating
By simply passing through the sticker on your water heater, it will clear you the power rating information of your water heater. The information on the label is critical when selecting a circuit breaker. You need to know that standard power ratings for most devices are given in watts. For the water heaters, the nominal power is 1,500-watts for residential use.

Know the highest current drawn by your heater
You need to be aware of the maximum current that your water heater will draw and this is done by dividing the power rating of your water heater by the operational voltage. For most water heaters with a constant power of 1,500-watts, with a voltage of 120, the maximum current intensity will be at 12.5 amps.

Decide on the Circuit Breaker Current Rating

How to Run a New Electric Circuit from a Breaker Panel
You must be sure of the ratings on your water heater by simply multiplying the maximum value of the circuit breaker rating by 125%. In the event your value happens to be minimal, you should go for a circuit breaker with the highest current notation. In case you need a circuit breaker with a nominal current of 15.6 amps, it is correct to go for the 20 amps which are the next in value.

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James Smith