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How To Change A Thermocouple On A Water Heater

Can I replace a thermocouple myself?

1 cause of pilot lights that won’t stay lit is a worn-out thermocouple. It’s easy to replace and a new one costs $5 to $10. Then detach the thermocouple from the burner and take it with you to the home center or hardware store to ensure you buy the right replacement.

How do you clean a thermocouple on a gas water heater?

Clean the thermocouple – using the emery cloth sandpaper, sand the ends of the thermocouple and then give it a finishing touch with the lint-free cloth. Hopefully, you can get to the ends of the thermocouple without having to detach it from the assembly, but you may have to do that.

How much should a plumber charge to replace a thermocouple?

Thermocouple – $20 to $150 The thermocouple is an apparatus that senses whether the pilot light is lit and triggers the gas control valve. Repairs typically cost about $150 to have it done professionally, though a new thermocouple itself only costs about $20 on average.

Are water heater thermocouples universal?

Universal Thermocouples. Universal thermocouples, as the name implies work on most water heaters. They are available online and in home supply stores for a reasonable cost. The length and the thread type are the two concerns when purchasing one.

How much does it cost to replace a thermocouple on a water heater?

The cost to replace the thermocouple on a water heater is $100 to $325. The thermocouple detects whether the pilot light is lit and signals the gas control valve to turn on the gas flow. Thermocouple replacement is the most common repair needed for gas tank water heaters.

How long does a thermocouple last on a water heater?

Thermocouples can last up to 10 years if properly installed and maintained, while furnaces can last 15-20 years, although either may wear out sooner in multifamily units.

How do I know if my thermocouple is bad on my water heater?

If the pilot lights but the flame goes out as soon as you release the button after holding it for 60 seconds, then the thermocouple is bad. It’s possible to replace the thermocouple without removing the burner assembly, and many repair people do this.

How do you get dust out of a thermocouple?

The best way to clean your thermocouple is to use either a piece of steel wool or the coarse side of a sponge to gently clean off any soot or other remnants. You can use a pencil eraser to clean between the threads of the screw that connects the thermocouple to the control valve of your system.

Why does my pilot light keep going out after replacing thermocouple?

If your water heater pilot won’t stay lit even after replacing the thermocouple, you most likely have a faulty gas control valve. It is a sign that the valve is failing to open and allow gas to flow to the pilot. You could also be dealing with a tripped or faulty thermal switch.

What causes a thermocouple to fail?

METAL FATIGUE Like everything, thermocouples can’t stay new forever. Changes in temperature can cause regular expansion and contraction in metal, which will cause thermocouples to weaken over time. After enough time, metal fatigue can cause a thermocouple to break.

What causes water heater pilot to go out?

Your thermocouple senses when your pilot light is burning. If it senses that your water heater pilot light keeps going out, the thermocouple will shift off the gas supply to the heater. Over time, thermocouples can malfunction, accumulate dust buildup, or the device can get bent away from the pilot light’s flame.

Should thermocouple be in pilot flame?

The pilot flame should touch the thermocouple at a specific level. If the flame is blue and weak, and barely reaches the thermocouple, it needs to be stronger. If it extends well above the thermocouple, it’s too strong. Install a new thermocouple by screwing it in, heating it up a bit, and then lighting the pilot.

Where is a thermocouple located on a hot water heater?

The thermocouple is part of the water heater’s burner assembly and is positioned next to the pilot light. It slides into a bracket and is held in place by a couple of clips. The thermocouple line runs outside the heater and is connected to the gas control valve, which is located on the outside of the tank.

Are thermocouples interchangeable?

Commercial thermocouples are interchangeable, economical, and supplied with standard connectors. Unlike most other temperature measurement devices, external form of excitation is not required for thermocouples because they are self-powered.

What does it mean when your pilot light keeps going out?

A faulty, misaligned, dirty, or damaged thermocouple is often the culprit behind your pilot light going out. The thermocouple is an automatic safety shutoff device that prevents the gas valve from opening if the pilot light is out.

Are furnace and water heater thermocouples the same?

While most furnaces and boilers have a thermocouple, in some boilers and gravity furnaces a thermopile (pilot generator) will generate electricity to operate the gas control valve. You can distinguish this device from the metal tube of a thermocouple by the two wires in sheathing that lead to it.