How to Replace an Electric Water Heater’s Heating Elements

In part one of the electric water heater blog, you learned how a water heater works, and how to troubleshoot some common problems. At the end of part 1, we promised we’d tell you how to replace the heating elements in your water heater. It’s a bigger job, but it’s also simple, straightforward, uncomplicated, quite elementary. You can probably do it yourself.

Since we keep our promises, here’s how to replace the heating elements in your electric water heater:

Getting Started

The first thing you should always do when you’re working on electrical appliances is turn off their power. To do that, head to your circuit breaker and flip the circuit associated with your electric water heater. This is important!

After you’ve turned off the power (make sure!), you should located the heating elements themselves. There are two, and they’re both in the water. You don’t have to go into the take to access them. Next, figure out which heating element you need to replace. If you’re only replacing the top heating element, you only have to empty the tank until it’s not in the water. If you have to replace both or just the bottom one, you’ll need to empty the whole tank.

Empty the tank

  • Shut off the cold water going to the heater.
  • Open the hot water faucet so air can get into the tank as it drains.
  • Connect a garden hose to the drain valve at bottom of the tank.
  • Place the other end of the hose so the water goes into a floor drain (or bucket).
  • Open the drain valve at the bottom of the water heater and drain the tank.

When the tank is empty (or empty enough to expose the top element), close the drain valve. Then, carefully disconnect the wires from the heating element.

Remove the heating element

You’ll need a wrench for this part. If the heating element is secured by bolts in a flange, use a wrench to remove the bolts. If it’s a screw-in type heating element, use the wrench to twist the element counter-clockwise until it’s loose. Whichever type you have, once it’s free, carefully pull the heating element out.

Once removed, use a wire brush or sandpaper to clean the tank around the opening for the element. You’re going to want all that gasket material, filings, and rust completely removed. You don’t want anything to get in the way of a perfect seal when you replace the element.

Now it’s time to buy the new heating element(s). Write down or take a picture of all the information on the water heater’s nameplate. Take that info with you to your neighborhood hardware store. You might even want to bring the old element so you can compare it to the new one. If you’re buying both upper and lower elements, you only have to bring one–they’re both the same.

Once you have your new element(s), it’s time to install the gasket(s).

Install the new heating element

Installing your new heating element is as easy as following the steps you took to take out the old one, backwards. If your old heating element was secured by bolts in a flange, you’ll have to tighten those bolts with a wrench.

Tighten the bolts the same way you tighten the lug nuts on a car tire: one nut sort of tightened, then a nut on the opposite side sort of tightened, same for the next one opposite that, etc. When all the bolts are “sort of tightened,” go ahead and tighten them all the way. Do not over tighten. Or, as dad said, “Tighten ’em as tight as you can, then give ’em one more twist.”

If it’s a screw-in type heating element, use a wrench to twist the element clockwise until it’s tight. Unless the new element tells you to, you don’t have to use Teflon tape on the threads.
Make sure the element is secured snugly against the tank opening, or the tank will leak from the opening.

When you’ve secured the element as snugly as possible, Open the cold water supply valve to fill the water heater. Make sure the hot water faucet is still open. At first, only air will come out of the hot water faucet. Soon, the hot water faucet will sputter air and dirty water. Continue filling the tank until the water from the hot water faucet runs clear without sputtering.

Turn off the hot water faucet

Check to make sure no water is leaking. If there is, tighten and repeat as necessary. If you can’t stop the leak, you’ll have to follow all of these steps again. Be sure to clean the tank opening and element to improve the seal between the element and the tank.

Once there are no leaks, re-connect the wires to heating element.

Note: The heating elements should be completely submerged in water before turning the power back on. If they’re not, your heating element will instantly burn out and need to be replaced. Make sure the elements are submerged!

Turn the power back on

When you do that, the water will start to heat up and the pipes to the hot water faucets will start filling up again. When that happens, you might get what’s called “water hammer.” To prevent that, make sure your hot water pipes refill slowly by opening the hot water faucets a little. You might also want to also remove shower heads, aerators from sink faucets and spray heads to prevent sediment from clogging them.

That’s it! You’ve replaced the elements in your water heater and you should have hot water again. Time for a nice, long, relaxing bath or shower. Good job!