Electric Water Heater Maintenance,
Maintaining Tips and How to
(updated 2018)

A DIY guide of the electric water heater maintenance and how cleaning and tune-ups can prevent or reduce problems such as the noise, sediment buildup, no hot water, not enough hot water, low pressure, stinky water, and other.

It is important to know that the properly maintained water heater ensures a good performance and efficiency, dependable, long-term and worry-free operation.

An electric water heater does not have a complicated design as the gas counterpart, so it is simpler and easier to maintain it. Some work can be done by the homeowner, while more complex, especially when the electrical work is involved, should be done by the licensed contractor.

If you do not want to read this step-by-step guide and just want it done - contact a plumber.

Maintenance checklist – what to check and required tools

• Storage tank
• Heating elements
• Thermostats
• Temperature and pressure relief valve - TPR
• Anode rod
• Dip tube
• Drain valve

First of all, our suggestion is to read the manufacturer’s manual carefully, the best will be a day before you perform the maintenance, so you can prepare all the necessary tools.

• Adjustable wrench
• Multi-meter
• Screwdriver
• Shop-vac
• Sandpaper
• Brush 
• Bucket 
• Garden hose
• Teflon tape

The basics - Visual inspection

The visual inspection is the first thing you want to do. This involves checking for any leaks, corrosion, obstructions, deformations and other unusual conditions. Leaking, for example, is mainly coming from the rusty storage tank and lose connections and it results in a water puddle at the base of the unit.

How to drain and flush an electric water heater

One of the major problems with the tank-type electric water heaters are the mineral sediments, dirt and deposits sitting at the bottom of the heater. Most of the user complaints are related to hard water, the main cause for this kind of a problem, which is affecting the efficiency, hot water output and durability of the heating unit. The hard water and corresponding problems are related mainly to home plumbing that is attached to the well systems.

What could prevent the sediment buildup within the heating system is the installation of the water softener. Of course, this has pros and cons.

If this is not an option, then the regular electric water heater maintenance might be adequate, if done properly and frequently. It is suggested by experts to drain 1-2 gallons every month and clean the tank from dirt. Draining is a simple operation which helps the heating system run smooth.

• The drain valve is located at the lowest point of the electric heater. Before you start the maintenance, turn off the water using the shut off valve, and electricity on the circuit breaker.
• You will need a garden hose and a bucket, and if water is still hot, gloves. Connect one end of the hose to the drain valve and the other to the floor drain or outside. Open the valve to release the water from the electric heater.
• Pressure relief valve needs to be opened, so air will get into the tank, and water can drain out smoothly. The other way is to open the nearby hot water faucet.
• Don't be surprised if you see dirty (brownish) water, it is normal. This is because of all the minerals and sediments that had built up.
• Depending on the capacity of the storage tank, it can several hours before the tank is empty.
• Flush the rest of the sediments out by turning on the cold water to the tank and turning off the hot tap. When the drained water is clear, you are done.
• To refill the tank again, close the pressure relief valve and drain valve and open the main water valve to let the water in. The tank has to be full of water before resuming the power.

You can also follow the detailed instructions found in the articles about draining and flushing.

How to clean the heating elements

Draining and flushing will also remove the scale build-up from the heating elements so the energy transfer is as high as when the unit was purchased. Draining/cleaning will also eliminate the hissing or singing sound produced when the heating elements are covered with the limescale.

Or, you can refer to this guide and check out how to remove the heating elements. Once removed, use a vinegar/water solution to remove the scale buildup.

Testing the thermostat

Use the multimeter to test the thermostats. Bigger water heaters have two thermostats, while smaller, with the capacity of fewer than 30 gallons - only one. Testing should include both. The idea is to check is there a power coming to the elements and tighten the wires if lose. Refer to an article about thermostats to learn more about installation, testing, replacing...

Check the settings on the thermostat – you want it in the range from 120-125 F, which is factory set to prevent scalding burns and reduce the high energy bills. If the water heater is older, you can put an insulation blanket around the tank and therefore reduce the energy loss.

Anode rod maintenance

An anode rod protects the water heater from corrosion. It is known as the sacrificial rod for a reason. It sacrifices itself (deteriorates) so the metal tank is protected from the aggressive water action. It is made of steel coated with magnesium or aluminum-zinc compound, softer material, so it can be used up before the metal tank.

It can last an average 5 years, sometimes longer (depends on the water quality and usage), so if not maintained regularly and replaced when needed, the lifetime of a water heater gets shorter.

A simple checking of an anode operating status, as part of the regular unit maintenance, can make the difference in the unit’s condition and performance. Also, the proper selection of an anode, when replacing the old, can make the difference between the rotten egg smell and no odor.

An anode rod, which is installed on top of the heater and submerged into the water can be easily removed for checking, using the right tool, such as the wrench or 1 1/16 socket (most often).

But before its removal, it is important to turn the power off on the circuit breaker and shut the water off on the main valve. Drain a few gallons of hot water through the drain valve, and only then you can remove it.

Inspect the rod and if more than 6” of the core wire is exposed on either side of the anode, replace it. Refer to an article that explains how to replace an anode rod and get more information.

Some manufacturers recommend frequent inspection – at least once a year, but it depends on the water quality, like hardness, and usage of the water softener.

Checking the dip tube

The dip tube or the cold water inlet is used to bring the cold water inside the water tank heater. Cheaper heaters have low-quality dip tubes, while more advanced have better dip tubes that can last longer and help in reducing the scale buildup inside the tank.

As the water heater ages, the dip tube, as the other elements, loses its functionality and can break, crack or split. So instead of bringing the cold water to the bottom of the tank, the deformed tube does it at the top of the heater, where it mixes with the hot water and delivering not as much hot water, resulting actually in cold showers.

As the element is brittle, it can break into small pieces, leaving the white fragments clogging the fixture aerators and other elements, affecting the unit’s efficiency and performance.

Taking into account the above, it is important to inspect the dip tube at least once a year, or when experiencing the problem such as described above.

Removing the dip tube for testing or replacing is easy, just follow the instructions.

Test the pressure release valve

It is extremely important to have the temperature and pressure relief valve working properly – because this is a safety element that will protect the unit from an extreme pressure development. It is not recommended for repairs.

It should be tested at least once in six months or often if there is a reason, such as a scale buildup due to hard water and well water supply.

If the water is dripping from the TPR valve, and cannot be closed properly, then it should be replaced.

If the TPR valve doesn't work, pressure, inside the tank can build up so high that will cause the damage, rupture of the unit, even explosion.

This is how a TPR valve should be tested:

• Shut off the electricity.
• Turn off the cold water supply to your electrical heater.
• Put a bucket under the drain tube of the pressure release valve.
• Lift the lever on the pressure release valve for a few seconds. If there is no vapor, air or water coming out, or it doesn't shut off, you have to replace it. Be careful with the vapor/water coming out is hot. Test the lever several times to ensure there is no debris which could prevent the valve from closing.
• Replacing the pressure release valve can be combined with the above step, when the tank is empty and before you flush the heater.

To unscrew the TPR valve use the pipe wrench.

What to do when on vacation

If the heater is to remain idle for a while (you are on a vacation or absent for some time, for example), the electrical power and water should be turned off. A water heater should never be left empty.

A proper electric water heater maintenance is essential for the efficient and economical water heating. It is not as difficult as maintaining the gas unit, but it still takes a few hours. With the above listed and explained procedures, maintenance becomes simpler, resulting in plenty of hot water and fewer problems and complaints.

Related articles

How to maintain a tank-type water heater
Maintaining an electric water heater
How to drain a water heater
How to flush a water heater
How to extend the life of a water heater
How to winterize a tankless
Cleaning tips
How to vent a gas water heater