How do you remove a thermocouple from a fireplace

The only tool you need to replace a thermocouple is a wrench. Turn off the gas supply to the gas valve. Use the wrench to unscrew the connector that holds the thermocouple to the gas valve, then unhook the probe from its clip and pull out the entire thermocouple assembly.

How do you remove a thermocouple to replace it?

Choose the new thermocouple based on the size and mounting style of the old one. …
Detach the old thermocouple as described above.
Remove the new thermocouple from the packaging and uncoil it to the appropriate shape.
Attach the new thermocouple to the pilot assembly and the gas valve.

How do I know if my thermocouple is bad on my gas fireplace?

The Fix: Pilot Light to Gas Fireplace Won’t Stay Lit So you’ve checked your pilot light and even reset it, but still, it wont stay lit. This can be an indication that your fireplace thermocouple is either bad or worn out.

Can you disconnect a thermocouple?

Realistically, you have just disabled the thermocouple, but you can also reach in and unclip it from its holding bracket where it meets the pilot light. In most cases it will be held on with a gravity clip, but some are held on with a screw that must be removed with a small screwdriver.

Can I replace a thermocouple myself?

The No. 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. Rather than trying to unfasten the thermocouple inside the water heater’s burning chamber, it’s easier to remove the whole burner and thermocouple assembly.

What is a thermocouple and what does it do?

Thermocouples are sensors used to measure temperature. It is a device used inside a gas furnace in Kansas, to assist the pilot light in keeping your furnace running and safe. … A thermocouple consists of two wires, or wire legs, made from different metals.

What are the symptoms of a bad thermocouple?

If you can’t get the flame to light at all, and you’re sure the gas is on, there’s probably an obstruction in the pilot tube. If the flame lights and goes out when you release the gas control knob after holding it in for the recommended 20 to 30 seconds, that’s the sign of a thermocouple malfunction.

What causes thermocouple to fail?

A good thermocouple is going to be used, and that can lead to metal fatigue. 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's 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. (On most furnaces, it also houses the button that you hold open or push to relight the pilot.)

Are all thermocouples the same?

From an operational perspective the thermocouples for a water heater are all pretty much the same. However, there are two variables, the length and the fittings used to install them, see below. A failing thermocouple will not send the correct electrical impulse and the gas valve will not release any gas.

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Do Thermopiles go bad?

Like the other component parts in your furnace, the thermocouple can wear down over time, producing lower voltage than it should when heated. And the worst part is that you can have a bad thermocouple without even knowing. Therefore, inspecting and testing your thermocouple should be part of your furnace maintenance.

How much is it to replace a thermocouple?

It costs $150 to $250 to replace a thermocouple. It checks to make sure the pilot light is on. It will shut the gas off if it’s not.

Why does the pilot light on my fireplace keep going out?

If the pilot light on your gas fireplace won’t stay lit, a very likely culprit is a component called a thermocouple. A thermocouple is a safety device and is a component of the ignition system. Its purpose is to not allow the gas valve to open if the pilot light isn’t lit.

Is a flame sensor and thermocouple the same thing?

People tend to use the terms “flame sensor” and “thermocouple” interchangeably. In truth, while they basically perform the same job, they’re not the same thing. If your furnace uses an electronic controller, it’s got a flame sensor. Thermocouples are used on standing pilot furnaces that have pilot lights.

How do you clean a thermocouple on a gas fireplace?

Turn off the fireplace gas valve and remove the front panel from the fireplace. …
Find the thermocouple, which is located next to the pilot light and looks like a small straight pipe.
Use a can of compressed air to gently blow away any dust and dirt from the thermocouple.

What does a gas fireplace thermocouple do?

Any gas appliance with a standing pilot needs a thermocouple to keep the pilot lit, whether it cycles on and off automatically, like a water heater, or you operate it manually, like a gas fireplace. The function of the thermocouple is to send a signal to the gas valve to stay open while the pilot is on.

How do I know what kind of thermocouple I need?

Determine the application where you will use the thermocouple sensor. …
Determine the temperature ranges the probe will be exposed to. …
Determine how important a fast response time is. …
Consider any chemical, abrasion or vibration resistance. …
Consider any installation requirements.

Will a pilot light on a thermocouple go bad?

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.