Checking Hot Water Heater Thermostat

Hot water is one of the few luxuries left that you can enjoy at least once a day. It is, therefore, crucial that you inspect your water heater’s thermostat to avoid a scare in the middle of your morning shower. Testing your thermostat is a mandatory activity, which will help you in locating many more problems associated with the water heater.

Many manufacturers produce thermostats based on the universal design; the upper thermostat will control both the upper and lower elements in the water heater. The lower thermostat will only control the lower element.

The upper thermostat uses the upper element to heat water at the top part of the tank and shuts it off when the water is hot enough. After it shuts down, the lower element turns on and heats the water in the lower part of the water heater. You will need tools such as a water heater tester and screwdriver.

How to Check a Hot Water Heater Thermostat

Here is a complete guide on how to check your water heater thermostat.

1. Ensure you turn off the water heater power off and remove the access panels, plastic safety covers, and any other insulation.
2. Use a screwdriver to turn set the upper thermostat at its highest possible temperature and the lower thermostat to its lowest temperature setting.
3. Turn the water heater power back on and use a multimeter to check that there is power coming to the water heater. The multimeter readings ought to be ranging between 220 and 240 Volts. If there is now reading on the multimeter, you have a faulty upper thermostat.
4. Now check the lower thermostat. Set the upper thermostat at the lowest temperature setting and the lower one at the highest temperature setting.
5. Check the lower thermostat for voltage and if there is power, allow the water to heat for a while and recalibrate the thermostat. If it clicks, it is good to go until the next check.
6. If you fail to get voltage readings on the element, place one of the probes on the top screw of the element and the other on the water heater tank. You ought to get a reading of at least 120V. Check the lower screw if it has power with one probe on it and the other on the water tank the reading ought to be the same as that of the upper screw.

The above guide is comprehensive to checking for a faulty water heater thermostat. If you do not get a reading on the multimeter or there is no clicking as you recalibrate the thermostat, you will have to replace the thermostat. Ensure to carry the faulty one with you when purchasing a new thermostat for reference purposes.

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