What you need to do before you start

Replacing a hot water heater element means removing the old heating coil or rod from inside the tank and installing a new one in its place. The job takes two to four hours and requires you to drain the tank, disconnect the electrical power, and unscrew the old element from a threaded port on the side or bottom of the tank. You do not need a plumber for this — the tools are basic and the steps are straightforward — but you do need to follow the safety steps exactly, because the tank holds hot water under pressure and the electrical connections can cause serious injury if handled wrong.

Before you touch anything, turn off power to the heater at the circuit breaker. Leave it off until you have finished and refilled the tank. If you are not certain which breaker controls the heater, turn off the main breaker instead. Do not skip this step. A live electrical connection inside the tank can kill you.

Key Takeaways

  • Turn off power at the circuit breaker before you do anything else, and leave it off until the tank is refilled and you have tested the heater.
  • Drain the tank completely through the drain valve at the bottom, which takes 30 to 60 minutes depending on tank size.
  • The element screws into a threaded port and usually requires a large socket wrench or element wrench to remove — a regular wrench will not grip it.
  • Elements cost between $15 and $50 depending on wattage and type, and you need to match the wattage and voltage of the old element exactly.
  • After installation, refill the tank slowly with the drain valve closed and bleed air from the hot water line before you restore power.

Gather the right tools and the correct replacement element

You will need a socket wrench or element wrench sized to fit the element in your tank — usually 1.5 inches or larger. A regular adjustable wrench will not work because the element is round and smooth and a wrench will slip. You can buy an element wrench at any hardware store for $8 to $15, or rent a socket set if you already own a ratchet. You will also need a bucket, a garden hose or length of tubing to fit the drain valve, towels, and a flathead screwdriver.

Before you buy a replacement element, find the old element's wattage and voltage. This information is printed on the element itself or on a label on the side of the tank. Most residential electric water heaters use 240 volts and either 4,500 or 5,500 watts. Do not guess — an element with the wrong wattage will not heat properly or may damage the tank. If you cannot read the label, take a photo of the tank's nameplate and bring it to the hardware store, or call the tank's manufacturer with the model number.

Drain the tank completely

Locate the drain valve at the bottom of the tank. It looks like a small faucet or spigot. Attach a garden hose to the valve and run the hose to a floor drain, outside, or into a large bucket. Open the valve by turning it counterclockwise. The water will be hot, so be careful not to touch it. Let the tank drain completely — this takes 30 to 60 minutes for a 40 to 50 gallon tank. Do not rush this step. If water is still in the tank when you try to remove the element, it will spill out and burn you.

While the tank drains, turn off the cold water supply to the heater. Look for a shutoff valve on the cold water line above the tank and turn it clockwise. If there is no shutoff valve, you will need to turn off the main water supply to the house. Once the tank is empty and the water supply is off, you are ready to remove the element.

Remove the old element

The element is mounted in a threaded port on the side or bottom of the tank. Use your socket wrench or element wrench to grip the element's hex head and turn it counterclockwise. It will be tight — the element is sealed with a rubber gasket and may have mineral buildup around it. Turn slowly and steadily. If the wrench slips, you may strip the hex head and make removal much harder. If the element will not budge after a few turns, spray the connection with penetrating oil and wait 15 minutes, then try again.

Once the element is loose, unscrew it by hand and pull it straight out of the tank. Inspect the rubber gasket on the element — if it is cracked, hardened, or missing, you will need a new gasket when you install the replacement. Most replacement elements come with a gasket, but check the package before you buy.

Install the new element

Before you insert the new element, clean the threaded port inside the tank with a clean cloth or paper towel. Mineral deposits or corrosion inside the port can prevent a good seal. Slide the new gasket onto the element if it is not already there, then insert the element into the port and hand-tighten it first. Once it is hand-tight, use your socket wrench to tighten it another quarter turn. Do not over-tighten — you only need enough pressure to compress the gasket and create a seal. Over-tightening can crack the gasket or strip the threads.

After the element is installed, close the drain valve at the bottom of the tank by turning it clockwise. Then open the cold water shutoff valve to begin refilling the tank. Open a hot water faucet somewhere in the house — usually the kitchen or bathroom sink — and leave it open while the tank fills. This allows air trapped in the tank and pipes to escape. Once water flows steadily from the faucet, close it and let the tank finish filling. This takes 10 to 15 minutes.

Test the heater and restore power

Once the tank is full, check for leaks around the element port. If water is dripping, turn off the water supply and tighten the element another quarter turn with your wrench. Refill the tank and check again. If the leak continues, you may need to remove the element and replace the gasket.

When the tank is full and there are no leaks, restore power by switching the circuit breaker back on. The heater will begin warming the water when ready. It takes 30 to 60 minutes for a full tank to reach temperature. Check the hot water faucet after an hour — if hot water flows steadily, the element is working. If the water is lukewarm or cold after two hours, the element may be defective or installed incorrectly. Turn off the power, drain the tank, and check that the element is seated fully in the port and tightened securely.

Frequently Asked Questions

How do I know if my water heater element is bad?

A bad element produces no hot water or very little hot water even after the heater has run for several hours. If you have power to the heater and the tank is full but the water stays cold, the element is likely burned out. You can also test the element with a multimeter set to ohms — a good element will show between 10 and 30 ohms, while a bad element will show zero or infinity.

Can I replace the element without draining the whole tank?

No. The element is submerged in water, and removing it will release pressurized water from the tank. Draining completely is the only safe way. Some people try to drain just enough to get below the element port, but this often leaves enough water to cause burns or damage.

What if the element wrench does not fit?

The element may have a different size hex head than you expected. Measure the width of the hex head with a ruler or caliper and buy the correct socket size. If the element is severely corroded and the hex head is damaged, you may need a plumber's element removal tool, which grips the element's sides instead of the hex head.

Do I need to replace the anode rod while the tank is drained?

The anode rod is a separate part that protects the tank from rust. It is not the same as the heating element. If your anode rod is corroded or missing, you can replace it while the tank is drained, but it is not required to replace it at the same time as the element. Check the rod's condition — if it is less than half an inch thick, replace it to extend the tank's life.

How long does a replacement element last?

A new element typically lasts 5 to 10 years depending on water quality and usage. Hard water with high mineral content shortens element life because minerals build up on the heating surface. If you have hard water, you may see elements fail every 3 to 5 years. Installing a water softener can extend element life significantly.