How To Install Electric Water Heater Wiring

How to Wire a Hot Water Heater

What if I told you that the average lifespan of an electric water heater is between 10-15 years? That implies that if you reside in your home for a decade, you will almost certainly have to replace it and connect the wiring to the new unit as well. Installing an electric water heater is not a difficult chore, and it is one that you will perform on a regular basis throughout your life, so why not learn how to do it yourself? You may learn how to wire a hot water heater without the assistance of a professional in this section.

Do not take any chances, and if you are unsure about what is necessary throughout this procedure, seek the assistance of a specialist.

Check out this useful article for further information on general electrical safety.

How to Wire an Electric Water Heater

Before you begin, you must determine whether or not electricity is already being supplied to the location of the water heater. If you are replacing a gas tank with an electric tank, you will most likely need to run wire (2-pole, 30-amp breaker with 10-2NM cable) from the circuit to the tank to complete the installation. If the circuit breaker has already ran a line to the position of the water heater, you can go to step 1. Otherwise, proceed to step 2. One more point to remember before we begin: do not fill the tank with water until the tank has been entirely wired, and do not switch on the circuit until the tank is completely filled with water.

Wiring a Hot Water Heater in 7 Steps

  1. Remove the cover from the junction box, which is most likely located on the top or side of the water heater. Most likely, you will only need to remove one screw in order to reveal two lead wires and a ground screw
  2. However, this is not guaranteed. Check the voltage- Never work on any electrical components without first ensuring that there is power to the device being repaired. If there is power present, the circuit is referred to be “live.” Please use caution! Performing wiring manipulation while the electricity is still running would not only violate the warranty, but it might also result in serious physical injury. If you are unsure whether you have a live circuit or not, it would be a good idea to use a voltage meter to verify whether there is electricity flowing through the lead wires of the circuit. If you discover that there is electricity, turn it off. This can be accomplished by tripping the GFCI breaker in the plug, if one is present (push the “TEST” button located in the center of the outlet). As a last resort, locate the relevant breaker in the power supply breaker box and turn it off. Remove the knockout- you will discover a knockout within the junction box, which you will need to remove. You may get rid of it by using needlenosepliers. Remove the wire insulation- if you installed the cable yourself, you may need to remove the plastic sheath in order to expose the wiring. Remove the wire insulation- ” (you need about 6″ to go within the junction box). After that, remove approximately 0.75 inch off the top “in the absence of insulation between the separate wires Fish the wiring- feed the wires through the ROMEX connector, then tighten and clamp the connection over the encased section of the NM cable (see illustration). There should be no exposed wires remaining on the premises. Pass the wires through the knockout, and then secure the ROMEX connection in place using a lock nut to prevent it from moving. Tip: Make sure that the Romex connector does not come into contact with any water pipes. You don’t want the temperature of the hot water outlet to interfere with your electrical work, so be sure it isn’t too hot. In order to connect the water heater to the circuit, you must first wrap the ground wire around the ground screw in the junction box and tighten it down. Connect the black wire from the circuit to the water heater, as well as any other wires from the water heater (twist together and secure with a wire nut). Take the white wire (the “hot” line) and wrap electrical tape over it to protect it from the elements (this is for identification purposes). This should be done at the breaker panel as well. After that, connect the white wire to the other wire that is located within the water heater. Replace the junction box cover—this is, in essence, the final stage in the process. Fill it with water and then re-energize the circuit breaker, and you’ll be able to use your new water heater.

Thanks for Choosing the Plumbing Experts

We appreciate you taking the time to visit us at Contact us if you have any queries concerning the wiring of your water heater or if you need any assistance. Remember, we sell well-known brands such as Bradford White, Takagi, Stiebel Eltron, and others. Purchase replacement components and water heater accessories from a variety of sources. Resources that are related to this topic include: Installing a Gas Water HeaterInstalling an Electric Water HeaterHow to Install a Gas Water Heater Soldering Water Heater Pipes – Step by Step Instructions Installing a Water Heater Expansion Tank is a simple process.

How to Install an Electric Water Heater

Installing a new electric water heater can allow you to save both money and electricity. How to do it is demonstrated in our video and step-by-step instructions. Please keep in mind that product pricing, availability, and item numbers may differ from market to market.

Before You Begin

Examine your water heater to see whether it need replacement or if routine maintenance would suffice. There might be a problem with the heating element or another type of maintenance issue if you are not getting hot water. Before committing to a complete replacement, conduct a brief maintenance inspection. If you have water on the floor or on top of the unit (as opposed to water leaking from a supply line above the unit), you’ll most likely need to replace your water heater as soon as possible.

A excellent time to think about upgrading or reducing your electric water heater is when your family’s size has increased or decreased.

If you’re not confident in your ability to complete water heater installation, hire a professional.

Caution The water pressure in your house is critical for all of the equipment that use water. A decrease in pressure reduces the stress placed on plumbing systems and helps to increase the lifespan of appliances and fixtures.

Water Pressure

Examine your water heater to see whether it needs to be replaced or if routine maintenance would suffice. There might be a problem with the heating element or another type of maintenance issue if you are not receiving hot water. Before committing to a full replacement, conduct a brief maintenance inspection. It’s likely that you’ll need a new water heater if you have standing water on the floor or on the unit’s top (as opposed to water leaking from a supply line above the unit). The data plate on your present tank contains information on the tank’s size and energy consumption, which makes it simpler to choose a comparable replacement unit.

Make sure you are in compliance with local building codes before beginning any work.

Caution For all water-using equipment, the water pressure in your home is essential.

Expansion Tank

Determine if you require a new water heater or if routine maintenance would sufficient. In the event that you are not receiving hot water, the heating element or another maintenance issue may be the cause. Before committing to a complete replacement, perform a brief maintenance inspection. It’s likely that you’ll need a new water heater if there’s water on the floor or on top of it (as opposed to water leaking from a supply line above the unit). The data plate on your present tank contains information on the tank’s size and energy use, which can make purchasing a comparable unit easier.

Before you begin, double-check your local construction codes to confirm that you are in compliance.

Caution The water pressure in your house is critical for all appliances that use water.

Removing the Old Water Heater

The following steps will walk you through the process of installing an electric water heater. When transporting a water heater, employ a helper, an appliance dolly, or a hand truck to ensure that the device is not damaged.

Preventing Scalds

Even with the temperature gauge set at 120 degrees, the risk of scalds remains a possibility. Children, the elderly, and individuals with delicate skin are particularly at risk of developing skin cancer. Consider adding thermostatic mixing valves to keep people safe from being hurt. Installed at the point of use faucet, fixture, or appliance, a thermostatic mixing valve regulates both the volume and temperature of water by connecting to both the hot and cold water supply lines at the same location.

The settings may be changed within the valve itself to offer the most comfortable experience possible.

How to install electric water heater

✔Use brass pipe, elbow and nipple when connecting copper pipe to galvanized pipeSave cost of plumbing repairs Prevent electrolytic corrosion/ deterioration of galvanized pipes and clogsUse 6 wraps teflon tape on threadsBuy:Brass nipples at AmazonBrass elbows at Amazon
XXStainless pipe, elbow and nipples corrode in softened water Use 6 wraps teflon tape on threadsBuy:Stainless nipples at AmazonStainless elbows at Amazon
TP temperature pressure release valve ✔ TP overflow tube runs down to at least 6 inches of floor. TP VALVE CODEOverflow tube must be same diameter as valve discharge connection. Do not downsize pipe into smaller pipe. Overflow tube can have maximum 4 elbows and 30 feet length.End of overflow tube cannot be threaded.Tube cannot be lower than top edge of drip pan. Tube must terminate 6″ above open drain. TP valve can draw water back into water heater if overflow tube is under water.Do not cap off TP valve or obstruct overflow tubeOverflow tube cannot have shut off valve installed, or any obstructive valveTP valve is first line of safety for water heater.TP valve releases water when pressure or temperature is too high, and prevents possible water heater explosionBuy:TP valves:Replacement TP valves at AmazonTeflon tape at AmazonResources:How to replace TP valveTP valve code
✔ Fill tank with water Open bathtub tap on hot side. When water runs fuull stream, then water heater is fullIllustration shows gate valve and ball valveRotate valve counter-clockwise to turn water ON✔ Check for leaks/re-inspect periodicallyBuy:ball valve/ water3/4″ ball valve at AmazonBrass ball valveBuy:Ball valve/ gasGas ball valve
Tank must be full of waterTest elements ✔ Tank must be full of water -or- elements burn out Fill water heater tank before turning circuit breaker ON,.Turn water ON. Open bathtub spout. Wait for full stream of water. Turn bathtub OFF. Lift TP lever for moment to bleed last of air from tank. Tank is full of water. Turn circuit breaker ON.Resource:How to test element
Automatic shut off valve ✔ Prevent flood damage/ automatic shut off valveSavings undetermined/ save massive damage to home Shut off water automatically when leak is detectedValve ataches to water line. detector sits on floor. electric power does not rely on batteriesBuy:Water detectors at AmazonAutomatic water heater leak shut off at AmazonResource:Leaking water heater/ steps
✔Tank must be full of water BEFORE power is ON✔ Push breaker fully OFF and then fully ON If breaker is faulty, more wires to another same-size circuit breakerResources:Troubleshoot new electric water heaterWater heater is tripping breakerHow to replace circuit breakerChoose correct wire and breaker sizeFigure volts amps and watts for water heaterNew water heater making noise
Larger image ✔ Push reset button located on upper thermostat, If water heater does not make bubbly fizzing soundPut ear against tank and listen for bubbly fizzing sound✔ Expect 19 gallon hot water per hour of heating240 volt 4500 watt element heats
✔ Suggest: Wrap water heater with insulationSave $2-8 per month Do not cover TP valve or discharge tubeInsulation blanket can cover entire electric water heater, including electric wireLeave access for drain valveMarathon water heater manual says not to cover top of tankBuy:Water heater insulation blankets at AmazonResources:See illustrationDept of energy resource
✔Suggest: Insulate pipesSave 25 cents – 1 dollar per monthx 30 years = $90-180Insulate pipes at water heater and rest of houseWater pipes lose heat. When colder water enters tank, it must be heated more.Pipes on top of tank draw heat out of water heater. Tank runs more.Gas water heater: Insulation must stay away from top of heater and vent pipe.Electric water heater: Insulation can cover all pipes and top of water heaterBuy:Pipe insulation at Amazon

What Are Some Basic Tips for Wiring Electric Water Heaters?

In most regions, a permit is required for the replacement of an electric water heater, regardless of whether the installation is carried out by a professional or by a homeowner. As part of the permit procedure, an inspector will check the work to ensure that the electrical and plumbing connections are made properly and safely, and that the installation conforms with the requirements of the local building code. We will only cover the fundamental electrical needs for a regular tank-style electric water heater, not an on-demand (tankless) water heater, in this section.

Turning off the Power

Make sure that the circuit that supplies the water heater is turned off before you check or touch any of the wiring or electrical connections on the water heater. In the majority of circumstances, a 30-amp, double-pole circuit breaker is used to protect the circuit. Switch off the relevant breaker in the breaker box, and then test the circuit at the water heater using an electrical voltage tester to ensure that it is not still active on the circuit.

Locating the Electrical Connections

When installing a water heater, the electrical connections are made at a junction box that is constructed into the water heater tank’s uppermost section. This is protected by a cover plate, which can be removed to allow you to see the wire connections on the interior of the enclosure. A flexible conduit or flexible metal cable, such as metal-clad (MC) cable, is typically used to encase the wire conductors running to the heater and protect them from damage. This flexibility gives a little amount of wiggle space, which makes it easier to repair the water heater, and it is a mandatory feature in many earthquake-prone locations, as well.

Understanding Water Heater Wiring

Electric water heaters necessitate the installation of a 240-volt dedicated circuit that serves only the water heater and none of the other appliances or devices on the circuit. In most cases, the circuit wiring will consist of a 30-amp double-pole breaker and 10-2 non-metallic (NM) or multi-core (MC) cable. If you have a black circuit wire, it should connect to the black wire lead on your water heater, and if you have a white circuit wire, it should link to either the red or white wire lead on your water heater.

The circuit ground wire is connected to either the green ground screw on the water heater or the ground lead on the water heater, depending on which is appropriate.

Heating Element Wiring

When replacing an electric water heater, you won’t have to deal with the thermostats or heating elements, but it’s important to know that electric water heaters also have internal wiring that runs from the wire connection box down the side of the tank to two different heating elements, each of which is controlled by a separate thermostat. Heat-generating components, as well as the thermostats that regulate their operation, are housed behind access panels that are positioned on either side of the water heater tank.

See also:  Why Is My Electric Tankless Water Heater Not Heating?

Unless you are changing a thermostat or a heating element on an existing water heater, you will not have to deal with any of these connection issues.

The Bonding Question

According to some construction codes, a bonding wire, also known as a bonding jumper, is required between the hot water and cold water pipes that serve the water heater. Keep in mind that the bonding jumper is not needed by the National Electrical Code or the Uniform Plumbing Code, but it may be required by your local building authority. If you have any questions, please contact your local building authority. It is possible that a bonding jumper will be necessary in order to guarantee a stable bond in a metal water distribution system.

In addition to this, the bonding wire is responsible for ensuring that the electrical grounding pathway on the water pipes is maintained.

No matter how you look at it, the most common bonding wire consists of a 6 AWG bare copper wire that is linked to a ground clamp on each of the hot and cold water pipes.

When replacing a water heater, it’s only a question of double-checking that the jumper connections are in place once the new water heater has been installed.

How To Wire A Hot Water Heater: An Ultimate guide

Please keep in mind that this content may contain affiliate links. This means that, at no additional cost to you, we may gain a small profit on purchases made via our links. After installation, the new heater will provide you with service for up to a decade before it has to be replaced. Now is the time to be ready and become familiar with the procedure before you begin.

Step By Step Guide For Wiring a Hot Water Heater

Immediately before you begin working with all of the essential wiring, you must first gather all of the necessary tools and equipment for the job. It is a vital component of this procedure since failing to include one of the components will result in you having to start over. Before you go out and buy a water heater, do some research to find out which one will satisfy all of your requirements. Only by purchasing the suitable heater will you be able to receive comprehensive servicing. You may go online for numerous buying tips on the best house water heaters to buy and then choose one that suits all of your requirements and budget.

Unless you remove the previous version, you will not be able to continue the procedure. Before you begin the process of replacing the old heater with a new one, you’ll need a few tools on hand. These are some examples:

  • Screwdriver, wrench, pipe cutter, dielectric connections, voltage testers, flexible hoses, sandpaper, and other related tools

With the help of these tools, you can now learn how to wire a hot water heater in your house without the need for specialized knowledge or support. The following are some of the steps you will take:

1. Disconnect the water heater from the electric source

Before you even begin to fiddle with the old heater, be certain that there is no electric current flowing through it to avoid being shocked. Neglecting to take this precautionary measure might result in serious consequences. It is best not to listen to all of those macho DIY manuals who operate on the heater without first turning it off at the circuit breaker. When it comes to wiring your electric heater, safety must always come first at every stage of the process. After you have turned off the electricity, use a voltage tester to see whether there is still any voltage going to the heater.

2. Drain all hot water

Continue by opening the faucet and allowing the hot water to flow out to drain any remaining hot water. The water must be allowed to drain until it becomes cool. In this phase, you will empty the hot water tank safely and without putting yourself in danger in the procedure. Keep in mind that the water in the tank is boiling hot, and you must always put safety first when working on any DIY project. After you have experienced the chilly water, turn off the water supply to the tank. The majority of the time, the supply valve is located at the top of the hot water tank.

Connect a hosepipe to the drainage valve and allow the water to flow into an outside tub for further safety.

3. Disconnect all the wiring on the old water heater

The third stage in the process of wiring a hot water heater is to disconnect all of the electric wiring that is connected to the top portion of the hot water tank. Disconnecting the cables ensures that you may securely remove the old heater and check for any wires that need to be replaced immediately after removal. A tester should be used to determine whether or not there is an electric supply to the heater once again. When disconnecting the cables, there should be no need to switch on the circuit breaker, right?

Furthermore, mark all of the cables as you disconnect them to make your job easier later on.

To make this easier, label the wire and snap a picture of it before starting to disconnect it are both good options to consider.

4. Disconnect all the piping system

Before disconnecting the hot water tank piping system, make sure it is in good working order. It is a necessary step in the process of wiring a hot water heater. Copper pipes may need to be removed from the system if any of the pipes utilized are made of this material. Other materials, on the other hand, are more comfortable to remove from the tank.

Remove the pipes that are attached to the tank using a wrench and inspect them for any that need to be replaced. If they are in good shape, you may save money by reusing them when you install the new water heater, which will save you money.

5. Install the new hot water tank

After you’ve disconnected the wiring and pipes, you may securely remove the old water heater from the house. Before installing the new water heater, you may check to see if there is anything else that needs to be replaced on the entire system before proceeding. Because the water heater is large and heavy, it should be moved with the help of a wheelbarrow or other moving equipment. If the load is too large, you can ask for help to avoid injuring yourself while attempting to lift it on your own.

  • Also, perform any necessary basic repairs to the space before proceeding with the installation of the new tank.
  • If they don’t, you may have some further work to perform before you can connect the new hot water heater to the electricity.
  • Make use of construction pieces that are more energy efficient, more inexpensive, and easier to put together at home.
  • When constructing a platform, take into consideration the height of the tank and the location of wiring.

6. Sand the copper pipes

Remember the sort of pipe that was used in the old water heater and prepare appropriately at this point. All copper pipes must be sanded before they can be used in the new tank installation. Using as much sandpaper as possible, polish the pipes until they are gleaming.

7. Wire in the new water heater

The new hot water tank should have been installed by now. The next step is to learn how to wire a hot water heater in your home. Remember, the procedure is straightforward and does not necessitate the use of a professional’s services at an additional cost. Take precautions and follow the instructions in this guide to get great outcomes. Remove the shell from the junction box on the new water heater in order to have access to the wiring. A green screw ground will be visible on the heater, and here is where you will attach the ground wire as the first stage in the wiring process.

  • After that, look to see if you can see a knockout on the tank’s uppermost section.
  • You can cut it with a pair of pliers if you have them.
  • It is preferable to complete this step by twisting and gaining access to the other wires.
  • This is the point at which the significance of shooting these photographs becomes apparent.

After that, you may secure the junction box with a screwdriver. Remember, though, to ensure that all of the wires are correctly connected before closing the junction box. If you fail to do so, it is possible that the heater may not function properly or will not function at all.

8. Attach all the pipes on the new water heater

It’s time to rejoin all of the pipes after you’ve mastered the art of wiring a hot water heater. It is necessary to reconnect the pipes that supply hot and cold water to the water heater at this point in order for it to work properly. Check all of the inlets and reconnect them as necessary. If the cold water intake is just connected to the cold water supply pipe, for example, the installation is complete. The similar procedure is used with the hot water pipes. At this stage, you must take extra precautions to ensure that the two do not become mixed.

  • You should have copper pies on the old one, and you should have them on the new one you’re installing as well.
  • Obtain hoses that are well-known for their flexibility in order to connect heater nipples to water supplies as well.
  • Additionally, they are simple to replace and are cost-effective.
  • Once you have finished attaching everything, double-check your work before moving on to the next step.
  • If you notice any leaks, you should address them first before continuing with the project.

9. Temperature and pressure discharge valve installation

At this point, the process of wiring a hot water heater does not appear to be as difficult as it formerly was. You’ve come this far, and you’re now in the last stretch. Another critical phase in the process is the connection of the discharge pipe. Purchase a discharge pipe and place it on the new water heater, making sure that the pipe’s end does not protrude too far beyond the floor. The proper measurement is approximately 5 inches from the bottom of the container. The temperature and pressure pipe/valve is a critical component of all water heaters, and it is responsible for extending their service life.

  • The pressure in the hot water tank can rise to dangerous levels, and it must be released immediately to avoid an explosion.
  • Check to make sure the valve you receive is the proper one for your water heater before installing it.
  • The user manuals that come with both of them will provide some insight into whether or not they are compatible.
  • Keep in mind that it must be at the proper height from the floor in order to operate properly.
  • After that, you may remove the temperature and pressure valves and wrap all of the threads with plumbing tape as an added measure of safety.
  • Once that is completed, reinstall the valve on the tank and tighten it down with a wrench to ensure that there are no leaks.

In addition, the valve has an open end that must always be pointing down at this point in order to function properly. You may now screw on an adapter and make sure that the threads are covered with plumbing tape because the pipe is now the right length for the job.

10. Switch on the power

As soon as you’ve completed the job, it’s time to put the entire heating system through its paces. It will assist you in determining whether or not you have mastered the art of wiring a hot water heater. Electricity is required for the new hot water heater at this point, and this is critical. Hot water heaters are rather specialized in that they require a circuit that is capable of handling 220 volts. In addition, you’ll need a 10/2 cable for the circuit as well as a circuit breaker with a 30amp rating.

Turn on the power supply by turning on the circuit breaker once you’ve filled the hot water tank and wait to see what happens!

It’s important to remember that you should never switch on the hot water heater if the tank is not completely full of water.

If the water is becoming hot and everything appears to be working properly, you have successfully installed a hot water heater.

Hiring a Professional vs DIY

With the help of this instruction, you will be able to wire a hot water heater on your own. Nonetheless, for other people, this may be a time-consuming process, and they would prefer to hire a professional. A DIY project needs a significant amount of effort and a basic understanding of electrical wiring. If you have the time, you can save money by doing it yourself. If this is the case, do not rush the job. It is preferable to employ a specialist and ensure that the heart is properly fitted. However, knowing how to finish the entire procedure on your own is a terrific confidence builder as well as an opportunity to acquire some new skills in the comfort of your own home.


Yes, it is possible to obtain it with minimum side effects. It is possible to connect a 220v heater backwards if the heater includes red and black wiring. In order to avoid water polarity concerns, you must verify that the hot water heater is properly wired in as much as is practicable.

How many wires on average does a water heater need?

An 8-gauge cable is required for a water heater rated at 30 amps. The gauge readings change based on the amplified signal.

Can I use 10 3 wire for a hot water heater?

You’ll need an 8-gauge wire for a 30-amp water heater. The gauge readings change based on the amplified signal received.

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Does a hot water heater need a ground wire?

A ground wire is required for a hot water heater, to be sure. It is a potentially dangerous equipment, and you must ensure that all safety protocols are followed in order to avoid mishaps. Electric shorts are conceivable from time to time owing to inadequate wiring, which can be life-threatening for everyone who uses the heater.


It is not as difficult as it appears to learn how to wire a hot water heater in the comfort of your own home.

However, it is not a procedure to be undertaken lightly, and great attention should be exercised when carrying out the installation. In order to avoid any mistakes that may be life-threatening, safety must always come first at every stage of the installation process.

How to Wire a Hot Water Heater to Breaker Box in 8 Steps

You’ve probably noticed that the rust in the critical regions of your water heater’s tank is starting to grow up. Do the obvious symptoms of wear and tear have an impact on the performance of your heater? If you answered yes, you must replace the gadget as soon as possible. A basic understanding of how to connect a hot water heater to an electrical panel is required. In most cases, you’ll need to use clean wiring when connecting your hot wires and ground wire to their proper positions within the heater and the circuit breaker.

What You Will Need

It should not be difficult to obtain the remaining materials if your electric water heater replacement has already been purchased. Before you begin wiring an electric water heater, make sure you follow the instructions in the list below and that you have the necessary sizes.

1. Circuit breaker

When water heaters degrade or when the amperage requirements of a new water heater change, it is critical that you replace your breaker. A standard 30- to 40-gallon water heater is compatible with a 30 or 40-amp electrical supply. Most homeowners choose 30-amps for their boiler tanks because it has the capacity to accommodate the ampacity of a water heater, including its maximum continuous load. Check the specifications of the replacement heater, however, to ensure that it will not cause a conflict with your breaker.

2. Electrical wires

The wiring for your water heater should be compatible with all of its components and safety devices, much as the wiring for your circuit breaker. A10 American Wiring Gauge is the appropriate wire gauge for water heaters since the common breaker size for water heaters is 30 amps (AWG). A 10-2 Non-Metallic Cable (NMC) is recommended for a 30-amp, 240-volt circuit, according to my recommendations. This type of wire is made up of two conductors and a ground, for a total of three wires in this configuration.

Each wire is black, one is white, and one is copper in color.

I strongly encourage you to label the wire with tape before you begin the task so that you will remember that it is a conductor.

3. Voltage tester

As a do-it-yourselfer with a basic understanding of how to wire a hot water heater, you should take personal responsibility for your own safety. A voltage tester or meter is an essential tool for protecting oneself from dangers such as accidentally touching a live wire without realizing what you’re doing. If there is no current, it will inform you with a simple flashing bulb method: green light for “no current,” red light for “live wire.” You’ll be ready to go as soon as you put this equipment together with body insulation such as rubber gloves and boots.

Steps on Wiring Your Water Heater to Breaker Box

Continue with the wiring of the hot water heater to the breaker box once you have properly assembled all of your tools.

As previously stated, if you are unsure about what you are doing, it is preferable to spend a few dollars on a professional rather than jeopardizing your life or the lives of your loved ones.

Step 1: Shut off the primary sources

Shutting off the main source of electricity should be the first step in any electrical repair procedure, as it should be in all situations. This method is required in order to be able to work freely with the wires without the danger of causing electrical problems. Alternatively, you may conserve water by turning off the main water supply line that supplies your home’s plumbing.

Step 2: Drain the excess water and depressurize

You should now be in a position to relieve pressure from your pipes after the flowing water has been turned off. To drain the leftover water from the pipelines, open one or two taps and allow the water to drain completely. Don’t forget to empty the pipes of both hot and cold water while you’re doing this. Allow them to run about for a few minutes.

Step 3: Install the circuit breaker

Before you begin installing the dedicated CB for your electric water heater, make sure everything is completely off the grid using your voltage tester. It is expected that no power will be accessible from every bus bar to the wire screws, and that your voltage tester will illuminate with a green signal. When you’re ready to go, gently connect the breaker to the bus bar until you hear a click.

Step 4: Run the wirings

Before you begin installing the dedicated CB for your electric water heater, make sure everything is off the grid using your voltage tester and other tools. With your voltage tester flashing a green light, there should be no power accessible from any bus bar to any wire screws. Then, when you’re ready to go, gently attach the breaker to the bus bar until you hear a click.

Step 5: Wire in the circuit breaker

Connect the wire with a gauge of 10 AWG to the circuit breaker. Remove a little piece of the cables from their bundles. Don’t forget to leave a sufficient length of wire and avoid cutting it all the way through. Begin connecting the hot wires on both poles of the CB by connecting them together. After that, screw in the ground wire to the appropriate location.

Step 6: Wire in the water heater

Connect the wires from the Electrical Metallic Tubing to the opening in the water heater’s junction box by fishing them through the hole. Strip the insulation for approximately.75 mm once you have secured your wires through the junction cover. Ensure that your wires pass through the ROMEX connection and that the NM cable’s sheath is clamped. Connect the ground wire to the ground screw on the interior of the junction box to complete the circuit. The black wire of your circuit should be wrapped tightly around a water heater wire to complete the twisting (you can pick any wire you want).

Locate the white wire on your panel and mark it with tape (to signify its status as a hot wire).

Step 7: Open the main pipe and fill the tank

Make certain that everything, from the PVC pipes to the electrical cables, is properly sealed, whether inside or outside the junction box.

First, turn on the water supply and fill the tank with water before turning on the electrical heating element. After that, depressurize the pipes by running all of your faucets for three minutes at a time.

Step 8: Turn on the main breaker box

Turn on the main electrical panel as well as the circuit breaker that is allocated to the water heater. To ensure the safety of your tank, utilize the voltage tester to discover any electrical leaks that may exist outside the tank. Metal elements such as junction covers and screws are subjected to inspection. Always check the water heating element, the top of the tank, and the bottom of the tank, to name a few reminders. In the worst-case situation, if frozen pipes develop, the heating element will continue to operate even if the water supply is low.

If you want a replacement, be certain that everything is identical to the prior configuration.


Did you have a good time while reading this tutorial? It is not as difficult as you may believe to understand how to connect a hot water heater to a breaker box. You’ll be alright if you match the breaker and wiring diameters to the electrical information on your tank, which you should do. For the record, if you are not comfortable with electrical wiring or plumbing work, contact a reputable professional immediately. Tell us what you think about this story in the comments section. You can express your thoughts and questions in the comments section below, and we will address them.

Electric Water Heater Installation: Step-by-Step Guide

If you’re the DIY kind, installing an electric water heater isn’t quite as complicated as it may appear at first glance. However, before starting the project, you should keep in mind that you will be required to perform some basic plumbing and electrical tasks. Even if these kind of jobs make you feel uncomfortable, there are several trustworthy companies that you may hire to install your new water heater. Nevertheless, if you’re up to the task, you may save money by doing it yourself. Generally speaking, electric water heaters have a life span of 8 to 10 years before they need to be replaced.

If you haven’t previously done so, you should troubleshoot the leak before investing in a new water heater.

Except if you discover that the leak is coming from the tank itself, you will have no choice but to replace the water heater.

Preparing to Install an Electric Water Heater

Having concluded that you want a new water heater, you may like to consult our buyers guide to assist you in selecting the most appropriate model for your needs. Furthermore, if you elect to install the water heater yourself, you will be responsible for removing your old water heater and properly disposing of it. Find Local Plumbing Professionals

Tools and Supplies

Installing an electric water heater is far less difficult than installing a gas water heater, but it is still a significant undertaking. Our recommendation is to hire a professional to complete the installation if you are unfamiliar with electrical and plumbing.

In addition, they will often dispose of your old water heater for you as part of the installation process. The following are step-by-step instructions for installing your electric water heater:

Disconnect the Electricity

First, we’ll have a look at what to do. Turn off the electricity to your water heater at the circuit breaker panel located near your water heater. Check the wiring of the water heater using a voltage tester to ensure that the device is turned off. Although it is not discussed in the video below, it is always a good idea to double-check that the water heater is not receiving any power after turning it off at the circuit breaker before doing any work on it. Start by turning on a hot water faucet and letting the water flow until it is cold.

The cold water feed to the water heater should be turned off (located at the top of the unit).

Drain the tank by opening the valve and venting it to the outside (or to a floor drain, or even into buckets).

You may also use the T P valve to your advantage.

Disconnect the Electrical

The next step is to disconnect the electrical cables from the water heater’s top. To begin, be certain that the circuit breaker in the breaker box has been switched off. Then, before you begin, verify the wires with a voltage tester to ensure they are in good working order. Cap the wires and name them (or take a picture of them) so that there is no confusion when you are connecting your new water heater in the future.

Disconnect the Plumbing

Step 4Disconnect the hot and cold water supply lines from the water heater. Copper plumbing may have been used in the installation of your water heater, and you may need to cut the pipes. If you need to cut the pipes, use a tubing (pipe) cutter and try to leave as much of the pipe as feasible intact as you can before cutting. If the discharge pipe from the T P valve is in good condition, you can remove it from the T P valve and reuse it on your new water heater.

Remove the Old Water Heater

4. Disconnect the hot and cold water supply lines from the water heater. Copper plumbing may have been used in the installation of your water heater, and you may be required to cut the pipes. In the event that you must cut the pipes, use a tubing (pipe) cutter and try to leave as much of the pipe as possible. As long as the T P discharge pipe is in excellent condition, you can remove it from the T P valve and use it on your new water heater.

Prepare the Plumbing Lines

4. Disconnect the hot and cold water supply lines from the mains. Copper piping may be used in the plumbing system of your water heater, and you may need to cut the pipes. If you have to cut the pipes, use a tubing (pipe) cutter and try to leave as much of the pipe as possible. In good condition, the T P discharge pipe can be removed from the T P valve and re-used on your new water heater.

Connect the Electrical Wiring

In order to gain access to the electrical cables, remove the junction box cover in Step 7. Attach the ground wire to the green ground screw using a crimp connector. Wire connectors are used to join the other wires together by twisting them together.

Make use of the prior wire connections as a reference and reconnect the wires in the same manner in which they were disconnected. Follow the directions on your label tags or the photo you took in Step 3. After that, reinstall the lid of the junction box.

Attach the Supply LinesTurn On the Water

Step 8: Connect the water supply lines for hot and cold water. Make certain that the cold water pipe is connected to the cold water intake on the water heater (it’s easy to make the error of connecting the cold to the hot water pipe). If your old water heater was plumbed with copper piping, you may want to consider plumbed it with copper piping once more. Flexible hoses, on the other hand, are highly recommended for making the connections. Not only is it more convenient, but it is also a suggested safety element in the event of an earthquake.

  1. Connect the flexible hoses to the nipples on the water heater using the hose clamps.
  2. When connecting flexible hoses to the hot and cold water pipes, we recommend that you use dielectric connections to prevent shock.
  3. By turning on the hot water faucet at the adjacent faucet, you may check for leaks in the flexible hose connections.
  4. Although this step is not discussed in the video, we recommend that you double-check your plumbing before continuing forward with the project.
  5. As soon as the tank is completely refilled, water will begin to flow out of the hot water faucet.
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Attach the T P Discharge Pipe

Step 9Connect the discharge line to the T P valve and tighten it. The pipe’s end must be within 6 inches of the floor in order to function properly.

  • Make use of a 3/4-inch male copper fitting. Paintpipe dope applied on the exterior of the fitting as well as the interior of the valve fittings. Tighten the fitting to the T P valve fitting once it has been attached. Remove the fitting from the pipe’s end and clean it
  • Soldering flux should be painted on the inside of the male fitting and outside of the pipe. Fitting the pipe to the fitting is completed. To join the pipes, solder and a torch should be used.

Turn On the PowerBleed the Hot Water Lines

Step 10After your water heater tank has been completely filled with water, switch on the circuit breaker located at the main power panel. Attention must be taken when turning on the electricity before the tank has entirely filled since the electric components may dry up if they are not totally immersed. This might cause irreparable damage to your electric heating components. Remember to switch off the circuit breaker before inspecting the electrical connections on your water heater if your water heater isn’t getting electricity.

Bleed Hot Water Lines

Step 11Allow the hot water tap to run for a few minutes until it stops “sputtering” in order to expel the air trapped in the tank and piping system. It may take many hours for the water in the tank to reach its maximum temperature. The temperature setting that is recommended is 120 degrees Fahrenheit. Let it sit for a couple of hours before checking the T P discharge pipe. If the pipe is dripping, it is possible that the pressure is too high.

Watch the Video

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Back It is recommended that you read the printed instructions that came with your water heater in addition to the material on this web site.

Read and observe any warning labels on the water heater, as well as the safety recommendations in the printed owner’s handbook, to limit the danger of property damage, serious injury, or death.


  • Toolkit includes: box cutter, marker, thermometer, non-contact circuit tester, paper towels or shop rags, pipe cutter, pipe joint compound or plumber’s tape, and other miscellaneous items. nutscrew and/or Phillips screwdriver and wrench (quarter-inch diameter)


  • If you have copper pipes, you should consider purchasing an Electric Water Heater Installation Kit (available at hardware shops and home centers), which includes compression fittings that do not require soldering. When installing plastic pipe in a residence, utilize threaded connections that are appropriate for the type of plastic pipe being used: CPVC or PEX (cross-linked polyethylene). Use of PVC or iron pipe is not recommended. Valve for shutting off the system
  • Thermostatic mixing valves are used in many applications.

Step3:Open Box and Remove the Water Heater

  • Cut along the dotted lines on the water heater box to make it smaller.

Step4:Read the Printed Installation Instructions and Labels

  • Using the dotted lines, cut the water heater box.

Step5:Install the Drain Pan

  • Install an appropriate drain pan that is connected to a proper drainage system. Make sure that the drain is installed such that the water level is confined to a maximum depth of 1-3/4″. At least two inches wider than the diameter of the water heater is required for a proper drain pan.

Step6:Install the Water Heater in the Drain Pan

  • Make sure you have a sufficient drain pan that is connected to a proper drain. Water should be able to reach a maximum depth of 1-3/4″ when the drain is installed properly. At least two inches wider than the diameter of the water heater is required for a proper drain pan installation.

Step7:Install the Temperature and Pressure Relief Valve

  • Almost all T P Relief Valves (Temperature and Pressure Relief Valves) are fitted at the manufacture. It is necessary to place your T P Relief Valve in the aperture labeled “T P Relief Valve” if it is included in a separate carton. Use the new T P Relief Valve that was included with your new water heater to relieve pressure. Do not use the previous one again
  • WARNING! If your water heater did not come with a T P Relief Valve (as well as a discharge pipe), install one (as well as a discharge pipe) in accordance with the printed installation instructions to avoid serious injury or death as a result of an explosion.

Step8:Install the Discharge Pipe

  • Install the discharge pipe in the appropriate location. The discharge pipe should have an internal diameter of at least 3/4″ and should be slanted to allow for efficient drainage. Install it so that the entire drainage system can function
  • The discharge pipe must be able to endure temperatures of 250°F (121°C) without distorting. Only copper, PEX, or CPVC pipe should be used. Use of any other form of pipe, such as PVC, iron, flexible plastic pipe, or any other sort of hose, is strictly prohibited. Finish the discharge pipe at least 1″ above a floor drain or outside, with a maximum of 6″ above the drain or outside. Instead of draining the discharge pipe into the drain pan, pipe it to a suitable drain instead. If you live in a cold region, you should connect the discharge line within the building to a suitable drain. Drains on the outside of the house might freeze and clog the drain line. It is not recommended to install any valves or other restrictions between the tank and the T P Relief Valve. It is not permissible to cap, block, plug, or insert any valve between the T P Relief Valve and the discharge pipe’s termination. Installing a reducer in the discharge pipe is not recommended.

Step9:Install Shutoff Valve

  • Install a manual shutdown valve in the cold water line that serves the water heater if one hasn’t previously been set up in that location. It is best to locate the shutdown valve next to the water heater so that it is easily reached. Only utilize a full-flow ball or gate valve that is suitable with potable water
  • The placement and piping of your water heater will determine how you complete this stage. Consult the installation manual for further information.

Step10:Install Thermostatic Mixing Valves

  • Install a Thermostatic Mixing Valve at each point of usage (for example, the kitchen sink, the bathroom sink, the bath, and the shower) in accordance with the manufacturer’s instructions. Always install a Thermostatic Mixing Valve or other temperature restriction mechanism in the inlet water supply line of a water heater that is fed by a solar water heating system (or any other pre-heating system) to limit the water supply input temperature to 120°F. WARNING! Water that is too hot can produce severe burns very immediately, resulting in serious damage or death. Ensure that there are Thermostatic Mixing Valves installed at each point of usage to minimize the danger of scalding.

Step11:Flexible Connectors are Easier to Work With

  • When connecting the water pipes to the water heater, compression fittings are used to make it easier to remove the water heater for servicing or replacement. To connect the copper pipes to the water heater when soldering copper pipes, utilize dielectric unions to connect the pipes to the water heater
  • It is possible to purchase installation kits that include flexible stainless steel connections and compression fittings that do not require soldering to be installed. Furthermore, many flexible connections are equipped with built-in dielectric fits. Ensure that the fittings you use are appropriate for the kind of pipe in your property. Pipes made of copper, PEX, or CPVC should be used. Use of iron or PVC pipe is not recommended. NOTICE: Do not solder pipes while they are connected to a water heater or while they are in use. The water heater’s input and output connections contain nonmetallic elements that might be harmed if they are not properly maintained.

Step12:Measure Pipes Carefully

  • Use the installation kit with flexible connections to measure both water lines if you are using a flexible connector installation kit.

Step13:Cut Water Pipes to Length

  • Reduce the length of both water pipes, but leave them a few inches longer than the specification. You may always shorten them if the situation calls for it.

Step14:Install Compression Fittings

  • Tighten compression fittings on both water lines after they have been installed. Take a look at this little video to learn how it’s done.

Step15:Pipe Joint Compound or Plumber’s Tape

  • Only use pipe joint compound or plumber’s tape on threaded connections
  • Do not use it anywhere else.

Step16:Connect the Water Supply

  • 3/4-inch hose is used to connect the cold water supply “To connect the output connection on the water heater marked “C” (cold), use an NPT threaded adaptor. 3/4-inch hose is used to connect the hot water supply “To connect the output connection on the water heater marked “H” (HOT), use an NPT threaded adaptor.

Step17:Check the Water Pipes

  • Examine and confirm that the hot and cold water pipes in the residence are connected to the appropriate hot and cold water fittings on the water heater

Step18:Dry the Pipe Connections

  • It is necessary to dry the pipe connections in order to detect any drips or leaks.

Step19:Turn the Cold Water Supply ON

  • Fill the tank with cold water by turning on the cold water supply again.

Step20:Remove the Aerator

NOTICE: Do not switch on the electrical power until you are certain that all of the air has been removed from the tank and that the tank is entirely filled with water. Using electricity before the tank is entirely filled with water will result in a dry fire in the upper element.

  • NOTICE: Do not switch on the electrical power until you are certain that all of the air has been removed from the tank and that the tank is entirely filled with water. It is possible that the upper element will burn out (dry fire) if power is introduced before the tank is entirely filled with water. Follow these procedures to remove all air from the tank and let the tank to entirely fill with water: Remove the aerator from the hot water faucet that is closest to you. All junk in the plumbing system is cleaned out of the pipes as a result of this.

Step21:Open a Hot Water Faucet

  • Open a hot water faucet and let the water to flow continuously until it reaches its maximum flow
  • Allow the water to run at full stream for THREE MINUTES in order to flush out all of the air from the tank. NOTICE: Before attaching electrical power to the tank, you must first remove all of the air from the tank and allow the tank to completely fill with water.

Step22:Close the Hot Water Faucet and Replace the Aerator

  • Close the hot water faucet and reinstall the aerator when all of the air has been removed from the tank.

Step23:Check for Leaks

  • Check for leaks at the input and outlet connections, as well as in the water pipes. Tighten the fittings and fix any leaks that may have occurred. It is almost always the case that leaks occur at connections and not at the tank

Step24:Check for Electrical Power

  • Check the power lines using a non-contact circuit tester to ensure that the power has been turned off completely. WARNING! Working on an electrified circuit has the potential to cause serious damage or death due to electrical shock. Check the cables with a volt meter or circuit tester to ensure that the power has been turned off

Step25:Install Wiring in a Conduit

  • Install wire in a conduit that has been authorized (if necessary by local codes)

Step26:Remove the Junction Box Cover

  • Disconnect the electrical connection box located on the top of the water heater by removing the lid.

Step27:Insert Conduit Connector

  • Insert the conduit connector and power wires into the junction box cover through the opening in the cover. Strain-relief nut should be attached.

Step28:Connect the Ground Wire

  • Using the bare copper or green ground wire from the house, connect it to the water heater’s green ground screw.

Step29:Connect the Home’s Power Wires

  • Connect the two power wires from the house to the two service wires from the water heater. Make the power connections by using wire nuts or other approved methods that are appropriate for the situation.

Step30:Replace the Junction Box Cover

  • Replace the junction box lid and fasten it with the screws that were provided
  • And NOTE: Make certain that the cover is properly attached to prevent the risk of fire and electric shock.

Step31:Install Strain Relief

  • When connecting the electrical cabling to the water heater, use a strain relief that is UL rated or CSA approved.

Step32:Turn Power ON

  • Power should be turned on at the circuit breaker (or fuses should be replaced). It may take several hours for a tank of cold water to get up to the appropriate temperature. If you still don’t have hot water after two hours, refer to the troubleshooting section for assistance.

Step33:Install Insulation on the Water Pipes

  • Water pipes should be insulated (or heated using heat tape), especially if the interior installation location is subjected to cold temperatures. Insulating the hot water line might help you save money on your energy bills.

Step34:Adjusting the Temperature

Thermal protection has been provided by factory setting the thermostat(s) on this water heater at about 120°F to limit the danger of scald injury. In order to supply hot water for automated dishwashers or washing machines, as well as to increase hot water capacity and decrease bacterial development, you may want to set the temperature higher.

  • Thermal protection has been provided by factory setting the thermostat(s) on this water heater at about 120°F to limit the danger of scald injury. In order to supply hot water for automated dishwashers or washing machines, to increase the capacity of the hot water heater, and to limit bacterial development, you may want to raise the temperature higher. WARNING! Because of the increased danger of scorching when the water heater’s thermostat(s) is set higher than 120°F, it is advised to install Thermostatic Mixing Valves at each point of use to lessen the risk of scalding
  • However, this is not required. Inspect and adjust Thermostatic Mixing Valves as needed at various places of usage around your home (for example, the bathtub faucet, shower, and lavatory sink)
  • If you really want to modify the temperature, you may do so by following the instructions in Standard Electric Troubleshooting: Adjusting the Temperature.

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