Installing An Electric Water Heater At Home: A Step-By-Step Guide

Installing an electric water heater is an excellent solution for those who are tired of dealing with an unreliable hot water supply or constantly repairing an outdated device. Even though the installation process may seem challenging, it is a DIY project that can save you a significant amount of money on installation fees.

In this guide, we will provide you with a comprehensive set of instructions, tips, and precautions to follow to ensure a successful installation of your brand new electric water heater. So, let’s begin upgrading your hot water system!

Electric water heater

Installing An Electric Water Heater: Things You Need To Know

Why Should I Install A New Water Heater?

There are several reasons why you should consider replacing your old electric water heater with a new one. Here are some of the most common ones:

  • Energy efficiency: Older electric units are generally less energy-efficient than newer models. This means that they consume more electricity to heat up the same amount of water, which can lead to higher energy bills. By upgrading to a newer, more energy-efficient model, you can save money on your monthly utility bills.
  • Cost savings: If your old heater is constantly breaking down or requiring repairs, it may be more cost-effective to replace it with a new one. The cost of repairing an old unit can quickly add up, and investing in a new one can save you money in the long run.
  • Improved performance: Over time, sediment and mineral buildup can accumulate inside your tank, which can reduce its performance and efficiency. A new model can provide you with a consistent supply of hot water and improve the overall performance of your home’s hot water system.
  • Increased safety: Older water heaters may be more prone to leaks, which can pose a safety hazard for your home. A new heater will come with updated safety features, such as automatic shutoff valves and pressure relief valves, to help prevent accidents and protect your home.
  • Better technology: Newer models often come with advanced features, such as digital temperature control and programmable settings, which can make it easier to manage and maintain your hot water system.
  • Increased demand. If your household’s hot water demand has increased and your current unit cannot keep up, it’s time to upgrade to a larger capacity tank. Models with a larger tank and higher First Hour Rating can ensure consistent hot water supply for your household.

The most important thing to keep in mind when installing an electric water heater is to follow local and national codes, standards, and manufacturer’s instructions. This ensures trouble-free and safe water heating for years to come. While it’s an easy DIY project that can be completed in one to two hours depending on your knowledge and skills, it does require basic plumbing and electrical skills.

If you need assistance or prefer professional installation, it is always best to contact a licensed professional who understands the local codes and requirements for proper hook-up.

Installing An Electric Water Heater Is Easy And Safe

Installing an electric water heater is easier and safer than installing a gas unit. Unlike gas units, there is no need for venting or gas installation, making it easier to locate them almost anywhere inside the house as long as the area is clean, dry, and free of flammable vapors.

Electric units do not require combustible fuels that can leak or explode, nor do they have pilot lights that can ignite flammable vapors or produce carbon monoxide that could backdraft into the living space.

Keep in mind that if you live in an earthquake-affected area, you may be required to install seismic straps to secure the water heater to the wall and prevent it from tipping over.

What Tools And Materials Do I Need?

Here is a list of tools you’ll need for successful electric water heater installation, most of which can be found in a handyman’s toolbox or garage:

  • Adjustable wrenches
  • Pliers
  • Screwdrivers
  • Multimeter (voltage tester)
  • Hacksaw or tubing cutter
  • Pipe joint compound, Teflon tape (depends on the pipe type: PVC, copper…)
  • Pipe cutter
  • Propane torch for soldering the copper pipes
  • Garden hose for filling the water and/or draining
  • Level
  • Wire strippers
  • Electrical conduit
  • Plastic twist caps
  • Manufacturer instructions

Step-By-Step Instructions

  1. Choose the right location for the water heater – The location should be easily accessible for repair, maintenance, and have enough space for the tank and connections. If you are replacing an old model, use the same spot.
  2. Shut off the power supply to your electric unit – Locate the circuit breaker for the unit and turn it off.
  3. Turn off the water supply to your heater – Locate the valve on the cold water supply pipe that leads to your heater and turn it off.
  4. Drain the old water heater – Use a garden hose to connect to the drain valve at the bottom of the tank and run the other end of the hose to a floor drain or outside.
  5. Disconnect the old water heater – Disconnect the electrical wiring, hot and cold water pipes, and any other connections. If the pipes are hard-plumbed, you must cut the lines, but if these are connected with the adapters, simply unscrew the connections. Remove the old unit and dispose it of properly.
  6. Place the water heater in the designated drain pan.
  7. Install the new T&P valve. Don’t use the old one. Install the discharge pipe.
  8. Prepare the device for installation – Remove the packaging and any plastic covers, remove the insulation around the heating elements, and remove the access panels.
  9. Connect the water supply – Install a new shut-off valve on the cold water supply line if needed, and connect the hot and cold water pipes to the water heater. Use Teflon tape or pipe joint compound on the threads of the connections. You might have to solder copper pipes.
  10. Connect the electrical wiring – Connect the black and red wires from the circuit breaker to the corresponding wires on the water heater. Connect the white wire from the circuit breaker to the white wire on the water heater. Connect the bare ground wire to the green screw on the water heater.
  11. Fill the water heater – Open a hot water faucet in the house and slowly open the cold water supply valve to the water heater. Allow the tank to fill completely and then close the faucet.
  12. Turn on the power supply – Turn the circuit breaker back on and wait for the water heater to heat up.
  13. Check for leaks – Check all connections for leaks, including the hot and cold water pipes, the relief valve, and the drain valve.
  14. Adjust the temperature – Use a thermometer to check the temperature of the water coming out of a hot water faucet. Adjust the thermostat if needed.
  15. Clean up – Remove any debris and packaging materials and dispose of them properly.

Choosing The Location And Some Installation Tips

  • The first step in this DIY project is to place the new water heater in a suitable metal drain, ensuring that it stands vertically and is level on the floor. The location should be near the center of the water piping system and in an area that is not subject to freezing, such as a garage, basement, or closet.
  • The drain pan must be at least 2″ wider than the tank and have a height of 2″ or more, with a drain included.
  • Ensure that the water heater is easily accessible and has enough space for servicing and maintenance, especially of the thermostat and heating elements.
  • Avoid placing the unit in an area where potential leakage can damage the surroundings.
  • Always turn off the water and electricity before beginning work.
  • The drain valve located at the bottom of the unit should be closed.

Plumbing Tips

  • The hot and cold water connections at the top of the unit are clearly marked and are 3/4 NPT.
  • Install the heat traps on the water heater if they are not already factory-installed, using Teflon tape or pipe compound to prevent leaks.
  • When selecting plumbing pipes, ensure they are suitable for potable water distribution, such as copper, CPVC, or polybutylene. For copper pipes, solder the threaded adapters to short pieces of copper pipe, then connect them to the water heater. Alternatively, use flexible steel braided pipes with shark bite fitting connections or PEX pipes. 
  • Use unions or flexible copper connectors for easy removal of the unit.
  • Ensure the hot water line is connected to the hot water outlet and the cold water line to the cold water inlet.
  • Check the local codes as some may require the installation of a mixing valve or anti-scald device, as well as the vacuum relief valve.
  • Install a shutoff valve at the end of the cold water supply, and a thermal expansion tank if the system is closed. The shutoff valve must not be located between the water heater and the expansion tank.
  • Install the TPR valve (temperature and pressure relief valve) with the discharge pipe near the floor and to the proper drain.
  • Connect the power lines and ground wire to the heater’s junction box behind the metal plate at the top of the unit, following the manufacturer’s installation guide.

Electrical Tips

  • Before installing the electrical wiring, check the diagram found on the water heater. The wires should run through the conduit, which is attached to the heater with the conduit connector. If the unit has a knockout hole, punch it out by using the hammer or screwdriver. Use a wire nut to connect a cable connector to the knockout hole. Connect the cable that runs from the electrical panel to the heater; red with red, black with the black (you can use the plastic twist caps), and bare ground wire around the ground screw found on the unit. 
  • Put the metal plate back to cover the wiring.
  • The proper overload fuse or circuit breaker protection must be installed.
  • Remove the thermostat plate and the insulation to reach the thermostat.
  • Set the thermostat to a temperature between 110 F and 130 F (43 C-54 C). Most of the time, the thermostat is factory set to approximately 120-125 F. You can keep it in that range.
  • Put the access plate and the insulation back.
  • Fill the tank with water. While filling the tank, make sure the hot water faucet is open for a minute or two to bleed the air from the water lines.
  • Check for leaks.
  • Turn the power on and make the necessary adjustments to prevent the burning scalds.

Note that by installing an electric water heater properly and maintaining it regularly, the unit can operate as designed and can last for a long time.

Warnings: Do not work on the heater before turning the power off. Do not turn on the unit when the tank is empty.


  • The power supply voltage must match the heater’s rating plate. Electric heater usually requires 220/240 V and between 30 and 60 amps.
  • The branch circuit wire and fusing or circuit breaker have to be of the proper size. Check the breaker that powers your heater. It has to be rated with enough amps and volts to carry the load.
  • Electrical connections must be tight and the unit properly grounded. Feed the electrical wires through the piece of conduit.
  • Before filling the tank, check your work first and ensure no leaks in the piping and all connections. Remember to close the drain valve before turning on the water.
  • When the tank is full, you should turn on the circuit breaker to send power to the heating elements. If you turn on the heating elements before the tank is full of water, they will be ruined due (known as the dry-fire) and will have to be replaced.


While this guide provides some fundamental information for installing an electric water heater, it is important to note that this is not a comprehensive resource. For more detailed information or specific questions about your particular installation, it is recommended to consult with a professional plumber or electrician.

We encourage you to explore the resources available on our website or other reputable sources to ensure a successful installation and safe operation of your electric water heater.

Also, if you experience problems such as no hot water, not enough hot water, rumbling noiserelief valve drippingleaking, and others, check out this troubleshooting guide.

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