How To Change Thermocouple On Water Heater

If your gas water heater's pilot light won't stay lit, in that location'due south a very practiced chance you demand a water heater thermocouple replacement.

I'yard going to tell you what a thermocouple is, what it does, the signs that it has gone bad, and how to replace it. Allow'due south get started.

What is a H2o Heater Thermocouple?

A water heater thermocouple is a sensor that turns off the gas supply when the pilot light goes out. This operational and safe feature is also known equally a flame or heat sensor and its office is to control the period of gas into the burner.

water heater thermocouple replacement - diagram how it works and parts — The key parts of the thermocouple are in this diagram. To work properly, the thermocouple should barely touch the flame from the pilot light. That's why they are located so close to each other. To pull out the quondam thermocouple, you'll need to loosen the bracket nut equally shown.

How Do You Know if Your Water Heater Thermocouple is Bad?

A bad thermocouple is the most common reason for a h2o heater airplane pilot low-cal that won't stay lit. And it's not unusual for information technology to vesture out.

Ironically, this happens sometimes due to the very nature of the device: the abiding change in temperature results in a worn-out or "stressed" thermocouple. Information technology can also malfunction when remainder or soot buildup causes the flame to exist blocked.

A bad thermocouple can outcome from the following:

A bent thermocouple: If the flame isn't slightly touching the thermocouple, it could be aptitude or misaligned. Simply bend information technology toward the pilot.
A dingy thermocouple: As noted above, soot or other balance tin can prevent it from working. To solve this problem, remove the thermocouple and clean it off. Caution: E'er turn off the gas valve before yous remove a thermocouple.
A cleaved thermocouple: This can event from wearing out. If electricity does not run through the thermocouple, information technology's broken. To exam this, employ a multimeter. If the voltage is less than 20MV, it is damaged and needs to be replaced. Read below for instructions on how to do that.

water heater thermocouple replacement - cleaning — A dirty thermocouple can be cleaned. Simply be gentle when cleaning. If this works, you lot won't have to supervene upon it.

H2o Heater Thermocouple Replacement: Instructions

1. Disconnect the Quondam Thermocouple

Plough the gas control knob to OFF and close the gas shutoff valve.
With an open-terminate wrench, loosen the nut that secures the h2o heater thermocouple to the command unit of measurement, then unscrew it.
Pull down on the copper atomic number 82 to detach the finish of the thermocouple from the control unit.
There may be a second nut attaching the thermocouple tip to the airplane pilot subclass; unscrew information technology and slide it back forth the copper lead.
Grip the base of operations of the thermocouple and pull firmly, sliding information technology out of the pilot bracket.

water heater thermocouple replacement - shut off gas — Earlier you practice anything else, plow the gas control knob to the OFF position.

2. Install the New Thermocouple

Purchase an verbal replacement for the old thermocouple from a plumbing supply center that carries your make or the plumber who installed your water heater.
Push the tip of the new thermocouple into the pilot bracket clip as far as it volition go.
If there is a hexagonal nut at its tip, spiral information technology to the bracket.
Run the pb out and bend it up into a gentle bend.
Screw the nut on the end of the thermocouple to the control unit past hand, then give it a quarter-plough with an open-end wrench.
Relight the pilot (instructions for relighting a pilot on all major brands is hither).
If information technology does not stay lit, close the gas shutoff valve, and telephone call for service.

Final Thoughts

A gas water heater thermocouple replacement is a project you can do yourself. Only it is of import that you follow the safety rules: (ane) turn off the gas is priority number one, and (two) don't touch the thermocouple until it has cooled down.

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Call 1-Tom-Plumber

Don't hesitate to contact us hither or call us at 1-Tom-Plumber (one-866-758-6237) if yous demand assist safely maintaining, repairing, or replacing your gas water heater.

1-Tom-Plumber's certified team of plumbers and drain technicians respond immediately to any emergency plumbing, drain cleaning, or water damage trouble. We as well handle the excavation of undercover water lines and sewer master lines. Our immediate-response squad is available every day and night of the twelvemonth, even on holidays.