How to Test and Change a Water Heater Thermostat?

Aug 03, 2023, 12:02pm

The thermostat of a water heater regulates the heating temperature of the water. It controls the heating resistor and cuts it when the required temperature is reached.

This thermostat is a potentiometer, a button that must be turned to choose the value. With use, it can become fragile. It also happens that the electrical aspect inside the room is faulty.

The thermostat should be replaced if you notice that the water heater no longer produces hot water, or if, on the contrary, the water is too hot. More generally, the thermostat can be the source of a problem related to the temperature of the water.

The water heater has few adjustment elements. The thermostat is often located behind a knob to be turned, on the part on which are arranged all the modules allowing the device to be configured (screen, buttons, etc.).

How to Test and Change a Water Heater Thermostat?

A malfunctioning water heater thermostat can leave you in the cold during times when you need hot water the most. It’s critical to know how to identify, test, and replace a faulty thermostat. This guide will help you understand the process in a step-by-step manner.

1. Identifying a Faulty Thermostat The most apparent sign of a faulty thermostat is when your water heater fails to heat water to the set temperature. It can either result in water that is too hot or not hot enough. It could also result in the water heater not switching off or not activating at all.

2. Safety Precautions Before you begin testing or replacing your water heater thermostat, turn off the power supply at the circuit breaker. Safety should always be the top priority when working with electrical appliances.

3. Locating the Thermostat In an electric water heater, there are typically two thermostats controlling the heating elements, one located at the top and another at the bottom. These thermostats are usually covered by an access panel. Remove the screws that hold the panel in place and gently take off the insulation behind it. You should see the thermostat attached to the tank.

4. Testing the Thermostat To test the thermostat, you will need a multimeter. Set the multimeter to the lowest Ohms of resistance setting, typically marked by the ‘Ω’ symbol. Then, place the probes on the terminals of the thermostat. If the multimeter reads zero, the thermostat is working correctly. However, if there is no reading, the thermostat is faulty and needs to be replaced.

How to Test and Change a Water Heater Thermostat?

5. Replacing the Thermostat First, take a picture or make a note of the wire connections to the thermostat for reference. Then, disconnect the wires from the terminals. Remove the thermostat from its bracket. It’s usually held in place by clips or screws.

Once the old thermostat is removed, place the new one in the same position and secure it with the clips or screws. Reconnect the wires as per the picture or note you took before.

6. Checking the New Thermostat After the new thermostat is installed, replace the insulation and access panel. Turn the power back on at the circuit breaker and let the water heater run for a while. Check the water temperature to verify if the new thermostat is working correctly.

Conclusion Replacing a water heater thermostat can be a relatively simple DIY job if done with proper care and safety. However, if you’re not comfortable working with electrical appliances, it’s always safer to hire a professional. Regular maintenance of your water heater can also help prevent issues like a faulty thermostat and ensure a consistent supply of hot water in your home.