Test Upper Thermostat Electric Water Heater

And when it comes to thermostats the device uses two of them generally.

Test upper thermostat electric water heater.

The upper thermostat has two functions. When this water is hot enough it shuts the upper element off. The structure of an electric water heater is pretty simple. Testing the water heater thermostat involves the checking of the heating element also.

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. If the opposite thing happens that means your thermostat has defected. The meter should read 0. If the water is hot enough at appointed temperature the meter won t show reading.

Before handling anything on the thermostat use a multimeter to confirm the power is off to the water heater. Test the water heater thermostat. However they do go bad and testing water heater thermostats is still required. In this case also check the current at the high limit switch.

The lower thermostat has only two terminals. Start by checking the thermostat terminals for the supply of power. To look for faults you will need to use a screwdriver. Touch one probe of the multimeter to each terminal on the lower thermostat.

Use the screwdriver to set the lower thermostat to the highest setting. One should be sitting on the top of unit 1. If you want to test a thermostat on an electric water heater you will also need to check the heating element. Connect the multimeter pin ends on point 1 2 as shown in the picture below.

To look at the faults in the upper thermostat you need to turn off the lower one. First it allows the upper element to heat the water in the top of the tank. This is important especially as open and grounded heating elements result in inaccurate tests. If you have a voltage stick you can use that as well.

If the water is cold the multimeter will point near zero. While the other is found right on the bottom. Using the multimeter connections touch the top to legs at the same time. Before you proceed further with the process of testing the heater thermostat take a screwdriver and the multimeter.

You will also need to check the water heater thermostat with digital multimeter tools. Leave the upper thermostat in the lowest setting and test the lower thermostat.