How to Install an Electric Water Heater: Step-by-Step Directions with Video

Install an Electric Water Heater

Electric water heater installation is a great do-it-yourself task. It really isn't as hard as you may think. If you're not afraid of doing some basic electrical work and plumbing, you can save yourself some money.

The average service life of a water heater is between 8 to 12 years. If your heater is reaching old age, you may want to consider replacing it with an energy efficient model​. That is especially true if your water heater is leaking.

How to Install an Electric Water Heater

Once you've decided that your only solution is to buy another water heater, it's time to get down to the job of installing a new one. Keep in mind, when the job is done, you'll have an old water heater to junk. This article will give you some ideas of how to get rid of it. 

Necessary Supplies

Step 1 - Remove the Old Water Heater

  • Turn off the electricity to the water heater at the electrical panel.
  • Check the water heater's electrical wiring with a voltage detector to make sure that no power is reaching the unit.
Install Electric Water Heater - Open Junction Box
  • Label the wires with tape to mark how they are connected. 
Install Electric Water Heater - Label Wires
  • Disconnect the wires.
  • Open a hot water faucet in the house, and let it run until the water is cool.
  • Shut off the cold water supply to the water heater.
Install Electric Water Heater - Turn off water
  • Connect a garden hose to the drain valve.
  • Open the valve and drain the tank.
  • Open a faucet to allow air into the tank.
Install Electric Water Heater - Drain tank
  • Remove the T&P discharge pipe from the T&P valve.
  • Set the discharge pipe aside to use later.
Install Electric Water Heater - Remove T&P Drain Line
  • Disconnect the water supply pipes.
Install Electric Water Heater - Disconnect Water Lines
  • Remove the old tank using a hand truck.

Step 2 - Install the New Water Heater

  • Set the new tank in a drain pan. 
  • Install the T&P discharge pipe to the T&P valve.
Install Electric Water Heater - Install the T&P Drain Line
  • Wrap the hot and cold heat trap nipples with plumbers tape.
Install Electric Water Heater - Line Nipples
  • Attach the flexible hoses to the hot & cold heat trap nipples. (Use the dielectric fittings if required).
Install Electric Water Heater - Connect Water Line
  • Line each end of the connector body threads with plumbers tape.
Install Electric Water Heater - line connecter
  • Attach one end of the connector body to the flexible hose.
Install Electric Water Heater - Attach connector
  • Hold the hose to the pipe, allowing for a little slack, and mark and cut the pipe.
  • Remove any burs on the cut pipe. 
Install Electric Water Heater - Connect the top of the water line
  • Slide the compression nut onto the pipe.
  • Press the pipe onto the connector fitting and tighten the compression nut.
  • Install earthquake straps.
Install Electric Water Heater - Earthquake Straps

Step 3 - Fill the Tank with Water

  • Remove the aerator from the nearest faucet and open the hot water side. 
  • Turn on the cold water supply to the water heater and check for leaks. 
Install Electric Water Heater - Turn on Water
  • ​Fill the tank full of water. When the water runs from the open faucet, the tank is full.
  • Leave the faucet open until it stops sputtering.
  • Do not connect the electrical wiring until the tank is completely full of water.
  • Remove the junction box cover and connect the green ground wire to the green ground screw. 
Install Electric Water Heater - Connect Ground Wire
  • Twist the wires together with wire connectors.
  • Follow the labels on the wires you marked when you removed them from your old water heater. 
Install Electric Water Heater - Connect Wiring
  • Replace the junction box cover and turn on the power at the electrical panel.
  • If your water heater does not have power, be sure to turn off the power at the electrical panel before checking your connections. 

    Watch the Video

    3 Reasons Your New Water Heater May Fail 

    A new electric water heater is a solid performer and will likely not give you any troubles for the next few years. However, there are a few things you should keep in mind before you cross it entirely off your list. Here are 3 common problems people run into after installing their electric water heater.

    1. Leaks - A leak is almost always a water supply connection. Double check all of your water connections.
    2. Upper Element - If your water heater tank isn't completely full when you turn the power on, the upper element will "dry fire" and burn out. If this happens to you, elements are inexpensive and relatively easy to replace
    3. Power - A power problem can be a number of issues. There could be a problem with the wiring in your home, or the voltage may be incorrect, it could also be as easy as flipping the switch in your breaker box. It's never a bad idea to call a professional.