How To Replace Water Heater Thermostat

If you’re experiencing problems with your water heater, such as not enough hot water or water that’s too hot, you may need to replace the thermostat. Here’s how to replace water heater thermostat in a few easy steps.

Step 1: Turn Off the Power

Before you begin, make sure you turn off the power to the water heater. You can do this by turning off the circuit breaker or removing the fuse that powers the water heater.

Step 2: Drain the Tank

Next, you’ll need to drain the tank. This will prevent water from spilling out when you remove the thermostat. Attach a garden hose to the drain valve at the bottom of the tank and run it to a floor drain or outside.

Step 3: Remove the Thermostat

Locate the thermostat on the side of the tank and remove the cover. You may need to use a screwdriver or pliers to do this. Once the cover is off, disconnect the wires from the thermostat and remove it from the tank.

Step 4: Install the New Thermostat

Take the new thermostat and attach the wires to the same terminals as the old thermostat. Then, place the thermostat back into the tank and secure it with the cover.

Step 5: Refill the Tank

Once the new thermostat is installed, close the drain valve and turn on the cold water supply to refill the tank. Make sure to open a hot water faucet to allow air to escape while the tank is filling.

Step 6: Turn On the Power

Finally, turn the power back on to the water heater by flipping the circuit breaker or replacing the fuse. Wait for the water to heat up and test the temperature to ensure it’s working correctly.

Frequently Asked Questions

Q: How do I know if I need to replace the thermostat?

A: If you’re experiencing problems with the temperature of your water, such as not enough hot water or water that’s too hot, it may be a sign that your thermostat needs to be replaced.

Q: Can I replace the thermostat myself?

A: Yes, you can replace the thermostat yourself if you’re comfortable working with electrical components and have the necessary tools.

Q: How long does it take to replace the thermostat?

A: The entire process should take less than an hour, depending on the size of your tank and the location of the thermostat.


Replacing a water heater thermostat is a simple process that can be done in just a few steps. By following these instructions, you can ensure that your water heater is working correctly and providing you with the hot water you need. Remember to always turn off the power before working on any electrical components and consult a professional if you’re unsure about any part of the process.