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Troubleshooting an Electric Water Heater

Troubleshooting an Electric Water Heater

Are you having trouble with your electric water heater and trying to figure out the problem? Water heater repairs are a big headache, and they can throw your entire home out of order. As JTS Management points out, knowing how to detect the root of the problem when a water heater malfunctions can be a great help.

How do you troubleshoot a water heater if it is not working? To do that, you must be familiar with the water heater’s components. You also need a step-by-step process for checking the water heater. This post provides the information you need to do all of these.

How to troubleshoot an electric water heater

Part one: Testing the water heater elements

  • Step one: Shut off the power

You need to locate the breaker that says “water heater,” “tank,” or “HWT” inside your circuit breaker box and flip it to the off position. You may also want to unplug the water heater from the wall if you can see the power outlet where it is plugged in.

  • Step two: Open the access panels

Remove the covers of the upper and lower access panels to reveal the element and thermostat. After you do this, you will want to remove the insulation. After, carefully remove the plastic cover over the part and thermostat.

  • Step three: Check that power is off

Before figuring out the problem with your water heater, you need to verify that the power is off. To do this, touch the electric wires inside the access panels with a volt-stick. If there is power in the water heater, the volt-stick will light up.

  • Step four:  Test the upper element 

Remove the two wires connected to the upper element and then do a resistance test to see if the upper part is working. For this, you will need a voltmeter. Simultaneously touch the voltmeter probes to the two terminals on the upper element where the wires were attached: one probe to one screw and the other probe to the second screw. If the meter registers resistance, the element is fine, but you need to replace the part if it registers no resistance.

  • Step five: Test the lower element

Repeat the above steps with the lower element

  • Step six: Test for grounded element

This test follows the same process as the ones already done. You will need the voltmeter, but you want to set it to ohms this time. Touch the probe to one of the terminals on the element and, instead of the other terminal, touch the second probe to the steel surface on the inner wall of the water heater behind the element. If the element is in good condition, the voltmeter will not register any resistance. If the voltmeter reads resistance, the element is grounded and needs to be replaced.

Part two: Testing the thermostat

The thermostat controls the heating element in the water heater. The thermostat maintains water temperature inside the tank by opening or closing the contacts that allow power to flow to the elements. If a water heater has two heating elements, it will also have two thermostats.

When testing the water heater thermostat for defects, you are looking for continuity. This is a continuous electrical path that should be present within the device. If there is no continuity, the thermostat is damaged and needs to be replaced. Here is how to test the thermostat in a water heater.

  • Step one: Getting ready

You will need a multimeter for this test. If using an analog multimeter, set the dial to the lowest level for ohms of resistance. Calibrate the meter by pinching the needles together and adjusting the needle to read zero. If using a digital multimeter, rotate the dial to the lowest level for ohms of resistance or resistance with tone.

  • Step two: Check the power supply and remove the access panel cover

Follow steps two and three in Part One above.

  • Step three: Reset the thermostat

The upper thermostat has a reset button; this can trip if the water in the tank is overheating. Overheating is often caused by thermostat contacts that have fused, shorted heating elements, or the thermostat is out of calibration. Push the reset button to reset the thermostat.

  • Step four: Test the thermostat

Isolate the thermostat from the circuit by disconnecting the wires. Note the position of each wire before you do this. Next, touch one multimeter probe to one left side terminal on the thermostat and the other probe to the other left side terminal. For digital meters, the thermostat is okay if the reading is zero (or almost zero) ohms. But if using an analog meter and there is no movement in the needle, the thermostat has no continuity and should be replaced. If all else fails, call a plumber for an electric water heater repair. In some cases a full replacement of your water heater may be in order.