Water heater temperature switch

You may think that only a professional can fix a water heater. However, many times a quick change of the temperature switch is all that is needed. In this post, we’ll explain why there is a temperature limit switch in a water heater, and how to replace it yourself!

What is the role of the temperature limit switch in your water heater? The temperature switch makes sure that the water heater doesn’t overheat. You should never bypass it, as that could permanently damage your water heater or start a fire. A temperature switch is a small but important part and repairing it easy enough for just about anyone to do. Click here to purchase your replacement switch!

Water heaters are an important part of a person’s home. If yours stops working, you’ll most likely notice quickly. There are two main types of water heaters, gas or electric. On a gas water heater, there will be vents that lead outside. If these vents get clogged, then the water heater can heat up to an unsafe temperature. This is where a temperature switch comes in. If the water heater gets above a preset temperature, then the contacts on the switch will open and the water heater will turn off. Water heaters use a manual reset switch, so the water heater will not be able to turn back on until a button on the switch is pressed. This ensures that someone looks at the water heater.

If the switch went off, but the vents are clear, then you should contact a professional. There may be an issue with the heater itself, which should only be worked on by someone who is trained. If you believe that the switch is the issues, then you can perform a continuity test on the switch to see if it is functioning properly.

How to Fix a Water Heater Yourself

432 Manual Reset Thermostat Switches, Surface MountKeep in mind, If you notice the smell of gas, leave the area immediately and call a professional.
You will want to test the continuity of your new switch before installing it to make sure that it works. If it doesn’t, touch the two ends of your continuity tester together to make sure that works.

  • First, Find the temperature switch on your unit. You may have to remove a cover. If you are having trouble finding it, follow the wires and see where they lead.
  • If you have a gas water heater, turn off the gas supply. Then set the thermostat control to “Pilot”, and then turn off the control valve.
  • Disconnect the wires from the temperature switch.
  • Use a continuity tester to see if the switch has continuity. If it does not, then it either needs to be reset or replaced.
  • If it needs to be replaced, then unscrew the switch from the water heater and remove it. Install the new just as the old one was.
  • Turn everything back on. Your water heater should be functional again.

For additional help on replacing your water heaters temperature switch, check out this great tutorial by AMRE Supply.

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The superior controls manufactured by Senasys have a history of solid performance in many industries. From 22.5 mm selectors, to the four quadrant lighted feedback CMC controls, almost any switching need can be, and has been utilized in a variety of applications. Select a group below for more information. When you have found a switch that fits your needs, simply fax or email your specs to us and let our highly trained engineers find the most efficient configuration for your applications.

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