Testing Water Heater Thermostat With Digital Multimeter

The lower thermostat has only two terminals.

Testing water heater thermostat with digital multimeter. If the multimeter needle moves the heater element is grounded and it must be replaced. You need to set the dial of multimeter to its lowest. Before handling anything on the thermostat use a multimeter to confirm the power is off to the water heater. In other words it should be on rx1k.

Now let us get started with the following steps on how to test a water heater with multimeter. There can be resistance with tone options as well that you can use. Leave the upper thermostat in the lowest setting and test the lower thermostat. Touch the other probe to any metal part of the water heater.

Usually it is on 200 in the digital multimeter. Hold the multimeter prongs to the element screws to test for flow. The reading on the multimeter should be zero. Water heater elements reading check.

Use the screwdriver to set the lower thermostat to the highest setting. If you have a voltage stick you can use that as well. Pull out the insulation and plastic of your water heater if it. If the water is cold the multimeter will point near zero.

Measuring the voltage of a water heater thermostat using a digital multimeter switch off the power breaker that power the water heater. If it is you will have a reading of 240v on terminals 1 and 3. Set the body of the multimeter on the ground at the base of the water heater. You will also need to check the water heater thermostat with digital multimeter tools.

If your multimeter points near zero then the thermostat is okay. Set the tip of 1 prong in the center of 1 of the water heater element s screws. The meter should read 0. Now have a look at the water heater s base part.

Touch one probe of the multimeter to each terminal on the lower thermostat. On left side screw terminal bring one of the black probes of your multimeter. Unless it happens the thermostat has defected. At the bottom of the water tank remove a metal plate to reveal the thermostat you suspect is faulty.

This basically means resistance times a thousand ohms. Connect the multimeter pin ends on point c d as shown in the picture below. Connect the multimeter pin ends on point 1 2 as shown in the picture below. Using the multimeter connections touch the top to legs at the same time.

Likewise take the second prong and hold it to the center of the water heater element s second screw.