Water Heater Thermostat Replacement

Posted by: Mas Broto
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Water Heater Thermostat Replacement

An electric water heater thermostat advises the heating elements when to begin warming up the water within the tank. A broken thermostat on a water heater is easy to fix. Follow these easy steps for water heater thermostat replacement.

Most electric hot water tanks have two elements and two thermostats, one of each on the top and bottom of the water tanks. The elements don’t warm up at the same time. The top element warms the water first, and only then will the bottom element begin to warm up.

The upper thermostat goes about as a facilitator between the two elements. When the water in the top part of the tank is sufficiently hot, it releases the lower thermostat to activate. When the lower thermostat detects the water is cool, it turns on the lower element. This happens when the upper element has finished warming the upper tank area.

To find out what is causing issues with your water heater, you have to test each element or thermostat. Once you have identified the issue, it’s time to repair or replace the water heater thermostat.

Water Heater Thermostat Test

The video guide below will show you several different tests on how to test a water heater thermostat. This will help you identify your particular problem and let you know if you really need to replace the water heater thermostat. You will need a multimeter to perform the test below. Unfortunately, there is no other way to perform this test without one.

Video by: RepairClinic.com

You will need access to the thermostat, so remove your cover panels for the top and bottom and remove the insulation. Some types of water heaters may also have plastic safety covers. These need to be removed also. The Lower thermostat has two terminals only, and testing is similar to how you test your upper thermostat. This is shown clearly in the video below.

When you have identified you need to replace your thermostat and purchase a replacement, you need to ensure you buy the same voltage currently being used. To do this, you can check your water heater tank label on the side for this information.

Keep in mind that upper and lower thermostats have different voltages, and it’s best to replace them simultaneously. If you have the owner’s manual to hand, I would recommend pulling this out and looking at the information provided. You could also take your current thermostats to your local hardware store for help.

Insure all-electric power is off before you begin any work at the mains of your home. Also, an additional extra is to turn off the electric supply of your water heater. Also, use a multimeter to check there is no electricity within the wires itself of the water heater.

DIY Water Heater Thermostat Replacement

Thermostat replacement is not too difficult. All it takes is a bit of time, some basic tools, and probably about 30 to 60 mins of your time. Again ensure you have the correct thermostat, as replacing it with an incorrect one can damage your water heater with more problems. With most water heaters, you should have switched all-electric currents off and removed the plates, insulation, and plastic shield before proceeding to the other steps below.

TIP! Take a photo of the wiring locations before you begin removing the wires (keeping a reference of this will help).

Step 1 Remove the Thermostat

Remove or disconnect all the wires, and in some cases, you will have a breakaway click. Check to see if there is one. If not, try to gently pull the thermostat away from the heater. Another form commonly used to secure the thermostat is a steel bracket on both sides.

Pull away one of the brackets gently with a screwdriver to release the thermostat. Then twist the thermostat to one side to release it from the bracket, and then you should be able to release it.

Step 2 Installing the New Thermostat

Installing is pretty easy, also. Ensure the area is clean and free from rust, and you can then pop in the new thermostat the same way you removed it.

Connect all the electrical wires to how they were before and replace the plastic cover, insulation, and outer cap. As you can see, hot water heater thermostats are quite easy replacements. With a little time, you can save yourself a bit of money.

Step 3 Turn ON the Power and Test

You can then turn on the power and test the system. You should now have the correct hot water temperature after the thermostat replacement.

How much does it cost to replace a thermostat in a hot water heater?

Replacing the water heater thermostat can cost about$25 to $50; the upper and lower could average around $10 to $25. To pay a professional for this service can cost around $150 in labor costs.

Water heater thermostat replacement is not a hard job to do, but you must keep safety first while working with electricity. I would advise replacing both water heating elements with a thermostat at the same time. If you are unsure about what to do, you better call a professional to get the job done.

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Mas Broto

Have been in the heating and air conditioning (HVAC) industry for over 20 years. He is person that will grow and thrive to learn more about the HVAC industry throughout his career. Mas Broto is also a blogger, who's dedicated to bringing you the best knowledge to get ahead in the game of life.

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