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.

Why does the pilot light on my gas furnace keep going out?

If your furnace pilot light keeps going out, it’s likely you have a broken thermocouple in your gas furnace. The thermocouple is a rod that comes into physical contact with the flame in your system. … When this component is not able to detect the flame, it will close the gas valve to prevent a gas leak in your home.

How do I know if my thermocouple is bad on my furnace?

A bad thermocouple itself can prevent a gas furnace or boiler from working – if you can light the flame at the pilot manually but then the flame goes out when you release the manual gas feed valve, the thermocouple is probably bad.

How do I stop my pilot light going out?

If you have a faulty thermocouple is the most common reason that your pilot light is malfunctioning. Over time your water heater will collect dirt, dust and other kinds of debris. Build up on your thermocouple can cause a malfunction. This is and easy fix, simply let it cool down and brush off the dirt or debris.

Why does my pilot light keep going out with a new thermocouple?

Thermocouple Issues Over time, thermocouples can malfunction, accumulate dust buildup, or the device can get bent away from the pilot light’s flame. In either case, the thermocouple will struggle to sense the pilot light and stop the gas supply.

How much does it cost 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.

Should a pilot light always be on?

Generally speaking, it is safe to leave your continuous pilot light on at all times, assuming it stays lit (more on this in a moment). While it does cost more to keep your pilot light on in between uses, it can actually have some benefits to your system.

How do you fix a gas fire that keeps going out?

1. Before You Begin: Is Your Pilot Light Lit Inside Fireplace?
2. The Fix: Pilot Light to Gas Fireplace Won’t Stay Lit.
3. Check Your Thermopile Output with the TH/TP Contacts.
4. Don’t Replace Your Thermopile or Thermocouple Right Away.
5. Cleaning the Thermopile.
6. Re-test the Cleaned Thermopile.

Does gas turn off when pilot goes out?

This is because all modern gas appliances with pilot lights have a fail-safe device that closes off the gas to the appliance in the case when the pilot may go out. … If the pilot light goes out for any reason, the current stops, the valve closes, thus preventing any gas from leaking.

Can a thermocouple be cleaned?

Yes, you can clean a thermocouple, but the task must be done with a light touch. Remove the thermocouple from the process assembly, using a steel wool or emery cloth, lightly clean the tip removing any build up.

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How do you bypass a thermocouple?

1. Move the tilts switch wire aside.
2. Remove your thermocouple from the heater using an 8mm wrench.
3. Pull the valve housing aside using your 13mm socket wrench. …
4. Remove the valve using your pliers. …
5. Put your thermocouple back into position.

How much does it cost to replace a furnace thermocouple?

Cost to Replace a Thermocouple on a Furnace Replacing a thermocouple costs $150 to $250, mostly due to labor time. On older models without an ignitor, it checks to make sure your pilot light is lit. If it’s not, it’ll shut the gas off.

Should I turn off pilot light in summer?

A little heat is produced when your pilot light is on so turning it off in summer can help reduce the heat inside your home. The less heat there is, the less you have to use your air conditioner needs to cool down the house. You can get savings and conserve energy if you turn off your pilot light.

How much heat does a pilot light give off?

Just how much gas does a pilot light consume? Most pilot lights will consume about 600 BTU’s of gas/hour. With 24 hours in a day, that’s roughly 14,400/BTU’s each day.

Does a pilot light give off heat?

Although the flame from a pilot light is small, it’s still heat. Depending on where you live, you might not want any extra heat being generated inside your home during the blazing summer months. A pilot light means heat, and it also means fuel usage.

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.

How long do thermocouples last?

How to Tell if You Have a Bad Thermocouple? 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 which thermocouple to buy?

You want to get one that is about the same length as the one you have. They are sold in in 6″ increments for the shorter lengths, 18″, 24″, 30″ and so on. For a water heater, 18″ and 24″ are common, although longer ones are possible. Remove the old thermocouple and measure it to see what length you need.

Why does my fire keep going out?

The ‘Fire Triangle’ taught us that fire needs three things to burn: oxygen, heat and fuel. … While the most common causes of log burners going out are insufficient oxygen, fuel or heat, stoves also rely on a properly functioning chimney. The purpose of this is to draw out exhaust fumes that could suffocate your fire.

How do you clean a thermocouple sensor?

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.

How do you troubleshoot a thermocouple?

Place one test lead on the side of the thermocouple and the other to the end that screws into the gas valve. If the thermocouple has proper continuity, a small resistance reading should be visible on the multimeter. Many multimeters also indicate continuity with an audio alert.

Can a thermocouple work intermittently?

In electrical circuits, the most unreliable points are electrical connections. So, if in a thermocouple circuit any of the connections suffer from corrosion or lack of intimate metal-to-metal contact, intermittent operation will result.

What is the purpose of a thermocouple in a gas furnace?

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. It works rather like a fail-safe to keep unburned gas from accumulating and burning, exploding or causing another type of health risk.

How much does it cost to keep a pilot light on?

Running a pilot light for 1 hour costs about 1 cent (0.62 cent/hour for natural gas and 1.64 cent/hour for propane). Monthly costs of running a pilot light range from $4.49/month (natural gas) to $11.34/month (propane).

Should the pilot light always be on in a water heater?

The thermocouple’s job is to shut a gas safety valve if the pilot light goes out. 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. After a while, the gas could collect in your home and become a health hazard.

Is it bad to turn your furnace off?

Heat constantly escapes your home when it’s cold outdoors, which is why it makes sense to lower the thermostat when you’re not there. But turning off the furnace in the winter—especially when you’re away for long periods of time—runs the risk of frozen pipes that could easily burst when they thaw.

Does pilot light use a lot of gas?

How much gas does a pilot light use? … Most pilot lights consume around 600 BTUs of gas every hour. If you leave your pilot light on for an entire day, it would roughly consume 14,400 BTU’s every day.

Can a pilot light start a fire?

When the appliance is turned on, a valve releases more gas, which is ignited by the pilot light. … If this leak continues, its concentration may reach a point where a spark – such as that from a cigarette lighter, static electricity, or even the pilot light itself as it is re-lit – will cause a fire or even an explosion.

How much natural gas does a pilot light use in a year?

A pilot light is a small flame that is kept lit to provide a catalyst for the main burner to be turned on when needed. The average fuel consumption of your standing Pilot light is: Natural gas is $0.60 a day = $219 a year. Liquid Propane is $1.80 a day = $657 a year.