The Buildup of Dirt or Debris Around The Pilot Light – Over the years it’s easy for dust, debris, and dirt to build up on the inside of the intake valve where the pilot light resides. This makes it difficult for the flame to breath and as a result causes the pilot light to go out suddenly.

What's the top reason a pilot light doesn't remain lit?

If your pilot light won’t stay alight, it might be the thermocouple. Sometimes dust buildup collects on the thermocouple and blocks the sensor. Try cleaning the thermocouple and then relighting the pilot light. If it continues to go out, the thermocouple might need to be replaced.

How do I know if my thermocouple is bad?

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.

How do I make my pilot light stay lit?

1. Make sure the thermostat is in heat mode.
2. Locate the pilot valve. …
3. Always turn the valve knob to the off position and make sure to wait at least several minutes for any residual gas to clear away.
4. Get your match ready. …
5. Once the pilot stays lit, turn the pilot valve to the on position.

Why does my pilot light not stay lit on my gas fireplace?

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.

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.

Can you clean a thermocouple?

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.

Why does my gas heater keep turning off?

If your furnace keeps shutting off, it could be due to low airflow. There are several indirect issues that cause low airflow. Dirty Air Filters. If you don’t change your air filters often enough, the filters will become dirty and clogged, which means the heat exchanger retains heat and eventually causes it to overheat.

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 often do thermocouples need to be replaced?

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.

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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.

Can you fix a thermocouple?

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.

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.

How do you remove a thermocouple from a gas 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.

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 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 much does it cost to fix a pilot light?

ServiceAverage cost to repairPilot light replacement$50 – $200Pressure relief valve replacement$50 – $300Thermocouple replacement$100 – $325Thermostat replacement$100 – $350

What do thermocouples do?

A thermocouple is a sensor that measures temperature. It consists of two different types of metals, joined together at one end. When the junction of the two metals is heated or cooled, a voltage is created that can be correlated back to the temperature.

Where is the thermocouple located on a furnace?

Your furnace’s thermocouple is usually located right in the flame of the furnace’s pilot light. Its copper tubing makes it easy to spot. The thermocouple is made up of a tube, a bracket, and wires.

What causes a gas water heater pilot light to go out?

Some of the most common reasons that water heater pilot lights go out include: A faulty thermocouple. … Over time, thermocouples can begin to malfunction and shut off the gas supply to the pilot light even if it’s burning properly. A bent or dirty thermocouple.

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.

How does a pilot light thermocouple work?

A thermocouple is a safety device that’s used to detect whether or not your furnace’s pilot light is lit. It contains a metal rod that is placed very close to your pilot light’s flame. … When your pilot light is lit, the heat from the flame sends a voltage through the thermocouple that keeps the gas line open.

How does a thermocouple work in a patio heater?

The thermocouple of a gas patio heater is a safety component designed to prevent gas leaks when the pilot goes out. It’s a copper rod that sits next to the pilot tube on the other side of the spark igniter; it allows gas to flow through the pilot tube when it detects heat from the pilot light.