How to Test Water Heater Element (with Video)

Electric water heaters use heating elements to heat the water within the tank. If you've noticed your hot water isn't as hot as it used to be, or isn't hot at all, you may have a problem with a heating element.  

This article will show you how to test a water heater element, and we'll also cover the symptoms of a bad heating element so you can rule out testing if it isn't necessary. 

Symptoms of a Bad Heating Element

Most electric water heaters have an upper and a lower heating element which are submerged within the tank.

Each plays a different role in heating the water, however, they both need to be working for your water heater to properly operate.

You may notice any of the following symptoms if one of the heating elements is bad:

• No hot water
• Lukewarm water
• Frequently running out of hot water
• Very little hot water
• Circuit breaker frequently trips

Upper Heating Element Symptoms

Since the upper and lower elements play a different role in heating the water, you can often determine which element is bad by the type of problem you experience.

If your upper heating element has failed, you'll typically experience one of the following:

• Luke warm water. (Hot water is not heating to the thermostat temperature)
• No hot water

Lower Heating Element Symptoms

If your lower heating element has failed, you may experience:

• Very little hot water
• Frequently running out of hot water

How to Test a Heating Element

In order to test your water heater's heating element you'll need a flat head screw driver and a multimeter.

Step-by-Step Guide

Step One - Turn off the power to your water heater at the electrical panel. This article will show you how.

Step Two - Use a flathead screw driver to remove the heating element cover. Then pull the insulation back so the thermostat is visible. You'll be able to see the head of the heating element within the thermostat. 

Step Three - With your multimeter switched to continuity, take the probes and place one on each screw of the heating element.

• Good Element: If your heating element is good, your multimeter will display a variety of different readings
• Bad Element: If your heating element is bad, your multimeter will display the number 1

Step Four - If the heating element is bad, it'll need to be replaced. You can do it yourself if you enjoy DIY projects, or hire someone to do it for you.

Watch the Video

What Causes a Heating Element to Burn Out?

Water heater elements can fail for a number of reasons. Here are some of the most common causes:

Sediment Buildup

Sediment buildup is one of the most common reasons a water heater element will go bad. 

All water contains minerals, and geographic areas with harder water contain higher levels of minerals.

As water heats, these minerals "break away" from the water and form a scale buildup or simply collect at the bottom of your tank.

If it's been awhile since you've drained the sediment from your tank, you may have a buildup of sediment that's covering the lower heating element. When this happens, it'll impact the transfer of heat to the water.

This causes the heating elements to work harder than necessary and can lead to a shortened service life. Draining the sediment from your tank a couple times a year will not only save your heating elements, but it'll also keep the tank itself healthy.

Dry Fire

Drying firing happens if the water heater is turned on without water fully covering the heating element.

This can happen if the water heater is turned on before the tank is at least 3/4's full, or a hot water tap isn't opened when filling the tank with water. In the latter case, an air pocket can form at the top of the tank which can prevent the upper heating element from being submersed in water.

When dry firing occurs there can be serious internal damage to the heating element. In most cases the heating element will need to be replaced.  

Power Surge

Although less common, if you experience a sudden voltage increase that exceeds the voltage rating for your heating element, it could cause the element to burn out.

When this happens, you'll need to replace your heating element.

Power surge protection tips:

• Inspect and repair wiring 
• Install a whole house surge protector
• Shut down the water heater during storms