When an electric water heater is not producing hot water or working very slowly, there’s likely a problem with the heating element. The key issue with conventional tanks is sediment buildup at the bottom and sides of the tank. This is especially common in areas that use very hard water. Over time, the sediments not only decrease the quality of your water but damage the heating element.
You can perform a simple test to check if a water heater element is still working. The primary tools needed are a screwdriver and an electric meter or a continuity tester. After completing the test, you’ll know if the heating element has to be replaced.
Your water heater element should last anywhere from 6 to 12 years, and in tankless water heaters, it can last up to 20. Despite the element’s longevity, it’s not a bad idea to carry out a routine test of your water heater element once annually to ensure it’s working properly.
Remember that your water heater will contain two heating elements, one at the top and one at the bottom. If the bottom element fails, you may still have hot water because the top element controls the thermostat. However, if the top element fails, you will likely notice a hot water shortage regardless of whether the bottom element is working. That’s why being consistent with your testing will help you catch any problems that are going unnoticed.
If you notice the red flags that signal an issue with the water heater element between your annual tests, that’s a strong indicator you’re going to need to replace the heating element. Warning signs to look out for include:
When these signals crop up, it’s time to gather the proper tools and begin the process of testing the water heater element.
When learning how to test a water heater element, it’s essential to make sure the power leading to the heater is off. Water heaters usually work off a 240-volt circuit which can result in serious electrocution if you begin working on the element with the power on. Always turn off the power at the fuse box before you start.
Then, you can double-check that it’s off using a voltage sniffer. First, check the voltage sniffer against the live wire to make sure it’s working. Simply touch the wire with the voltage sniffer. It will produce a loud beep.
Then you can test the wires coming into your water heater at the top of the tank. Touch the wires with the voltage sniffer. There should be no sound at all, which means there’s no power going to the water heater.
Using a small screwdriver, remove the metal cover to access the element. There is usually a piece of spray foam insulation, which has to be removed as well. Once you have removed these two covering pieces, you’ll see the wires connecting to the element. Finally, disconnect the wires with the screwdriver.
Once you remove the cover and the insulation, you’ll notice the heating element and the thermostat. The thermostat has a rectangular shape, and the visible part of the heating element is circular. The thermostat will be on top, sitting flat against the tank. It’s what figures out how hot the tank is and if the heating element needs to turn on.
The thermostat will have two wires coming from the top of the tank and two thicker wires leading to the heating element right below it.
When learning how to test a water heater element there are two key tests. One checks if the element is broken, the other one checks if the element has a short. For both tests, you can use a continuity tester. You can also use an electric meter, which should be set to continuity.
To make sure the continuity tester battery is working, simply touch the alligator clip with the probe. The continuity tester should light up.
To see if the heating element is broken, attach the alligator clip to one of the screws on the heating element, and touch another screw with the continuity tester probe. If the heating element is working, the light on the tester should turn on.
Attach the alligator clip to one screw and directly touch a metal part on the water heater with the probe. There should be no light on the continuity tester. If there’s light, it means the element is shorted. Repeat the same process on another screw. If the water heater has heating elements, you should also repeat the test on the other element.
When finding a broken or shorted heating element, you’ll want to replace it with a new one. Before changing the heating elements, the tank will have to be drained. The heating element is in direct contact with the water, so taking it out without draining it will flood the room.
If you determine that your water heater element is broken or shorted and needs to be changed, you can either call in a professional or perform the repair yourself. It’s not a complicated process, and many homeowners choose to take on the task themselves to save some money.
However, if you’re uncomfortable handling technical repairs, it’s always a safer option to hire someone with more experience to do the job.
Performing this heating element test is easy, and it will take you less than an hour. Having solved the problem with a new heating element, one can enjoy hot water once again. Once the heater is working with a new heating element, it’s important to clean and flush it once a year. This prevents future problems and prolongs the lifespan of the new heating element.