Test Upper Thermostat Electric Water Heater

To look for faults you will need to use a screwdriver.

Test upper thermostat electric water heater.

The upper thermostat has two functions. Leave the upper thermostat in the lowest setting and test the lower thermostat. Use the screwdriver to set the lower thermostat to the highest setting. Before handling anything on the thermostat use a multimeter to confirm the power is off to the water heater.

The meter should read 0. Connect the multimeter pin ends on point 1 2 as shown in the picture below. Touch one probe of the multimeter to each terminal on the lower thermostat. If you get the reading of 240v on terminal 1 and terminal 3 then the power is on but if you get no readings then the power is off.

Test the water heater thermostat. Testing the water heater thermostat involves the checking of the heating element also. If you want to test a thermostat on an electric water heater you will also need to check the heating element. When this water is hot enough it shuts the upper element off.

Using the multimeter connections touch the top to legs at the same time. In this case also check the current at the high limit switch. The lower thermostat has only two terminals. Your water heater usually has two elements and two thermostats.

If you have a voltage stick you can use that as well. While the other is found right on the bottom. This is important especially as open and grounded heating elements result in inaccurate tests. If the water is cold the multimeter will point near zero.

If the opposite thing happens that means your thermostat has defected. You will also need to check the water heater thermostat with digital multimeter tools. The structure of an electric water heater is pretty simple. And when it comes to thermostats the device uses two of them generally.

Before you proceed further with the process of testing the heater thermostat take a screwdriver and the multimeter. First it allows the upper element to heat the water in the top of the tank. The reading on the multimeter should be zero. However they do go bad and testing water heater thermostats is still required.

If the water is hot enough at appointed temperature the meter won t show reading. One should be sitting on the top of unit 1.