Why does my thermocouple keep going out?

It’s Dirty. Soot buildup on the thermocouple may block the flame. Under constant exposure to a hot flame, a thermocouple wears down over time. Even a slight residue can make the thermocouple malfunction.

The thermocouple unwinds and switches on the fireplace. Thermocouples are rigorously tested and should last for years. Indeed, experts believe a four-year check cycle is all that is needed to make sure things are functioning properly.

Additionally, what would cause a pilot light to keep going out? Usually, a problem with the thermocouple causes the pilot light to go out. The thermocouple is the small copper rod that the pilot light hits. That’s important because gas is always being supplied to the pilot to keep the flame lit. But if the pilot flame goes out, then the gas would still be released.

Also, why do thermocouples go bad?

The thermocouple can do this because, in its probe, it contains two different metals, and a voltage is generated when one of them is heated. This is the result of a phenomenon known as the Seebeck Effect. Nothing lasts forever, and when the thermocouple wears out, the pilot won’t stay lit and your appliance won’t work.

Do thermocouples wear out?

Thermocouples wear out and are replaceable, but you should conduct a few simple tests before doing that, because your gas pilot may be going out for another reason. The thermopile is a related device that you should test at the same time — its function is to open the gas to the burners.

How do I know if my thermocouple is bad?

This means that if the thermocouple goes bad, there is no way of detecting if the pilot light is burning or not. And when the pilot light goes out, you will not have hot water supply in your plumbing system. To test if the problem is with the thermocouple, try to relight the pilot.

Can I fix a thermocouple?

A burned out or broken thermocouple should be replaced. To replace a thermocouple: Step 1: Unscrew the copper lead and the connection nut inside the threaded connection to the gas line. Step 2: Under the mounting bracket at the thermocouple tube, unscrew the bracket nut that holds the tube in place.

How do you test a thermocouple?

Steps Locate the pilot light controls on the gas valve. Turn the pilot light on for 30 seconds. Release the button to see if the pilot light goes out. Turn off the gas supply to test the thermocouple again. Count to 20 and wait for the pilot light to go out. Listen for clicking near the gas valve.

How much does it cost to replace a thermocouple?

Thermocouple Replacement – $20-$150 Calling a professional plumber to install a new thermocouple should only be up to $150. If you do the work yourself, you will only pay the price of the part which is about $20.

What does a thermocouple look like?

The thermocouple looks like a piece of metal tubing smaller than a soda straw. To find it, first locate the gas control box. This is the box that the main gas line enters, where you turn the gas on in the furnace. The other end of the thermocouple sits in the flame of the pilot light.

Does the length of a thermocouple matter?

The length of a thermocouple has no effect on its measurement accuracy or its ability to transfer the signal to the instrument. In other words, thermocouples do not experience “voltage drops” or power loss along its length as a high current power line might possess.

Are 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.

Should a thermocouple be in the flame?

Typically the thermocouple sensor is mounted right in the flame of the pilot light on gas fired heating equipment. But not all of these systems use a thermocouple. Some gas fired heating equipment relies on an electronic ignition to ignite the flame. Those devices generally will not use a thermocouple.

Can a thermocouple leak gas?

Without a thermocouple, it will seep tiny bits of gas into the combustion chamber of the device. In a few hours, it can leak enough gas for a small explosion, probably just enough to shorten your eyebrows.

Can you overheat a thermocouple?

If the back end of your thermocouple bulb gets constantly overheated, it will fail. With excessive back pressure coming from the burner ports, thermocouples can get burned up quickly.

How do you replace a thermocouple?

How to Replace a Water Heater’s Thermocouple Turn off the gas supply. Unfasten the three nuts that hold the thermocouple and the two gas tubes to the valve. Detach the thermocouple from the burner. Install the new one the same way that you removed the old one. Turn the gas back on and follow the lighting instructions on the water heater.

Will a pilot light stay lit with a bad thermocouple?

A thermocouple senses the heat of the pilot and allows gas to flow to the burner. A bad thermocouple will shut off gas to both the pilot and the burner so the pilot light won’t stay lit.