Why does my heater pilot keep 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.

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.

Why won't my pilot light stay lit on my gas heater?

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.

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.

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 going out?

The heater won‘t operate properly if the pilot flickers, is too weak or goes out, and the cause could also be blockages in the pilot tube. Another cause of a weak pilot is a faulty thermocouple. It’s a heat sensor placed next to the pilot flame that signals the gas valve to stay open when the flame is burning.

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.

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 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

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

Most furnaces with electronic ignition have a device called a hot surface igniter. … The difference is that the flame is only lit (by an electronic spark) when your furnace is ready for a heating cycle. When the pilot light is not needed, it is completely off, saving you money on gas.

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 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.

Can I bypass a thermocouple?

Can You Bypass Thermocouples on Patio Heaters? Constant heat supply ensures that your patio heater pilot light is lit at all times. If your unit is receiving no heat, this won’t be so. To temporarily sort the situation, you can bypass thermocouples until you have funds to replace them.

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.

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.

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.

Are thermocouples universal?

Honeywell, White Rodgers, and other manufacturers make universal replacement thermocouples, usually with a 30-millivolts (mV) rating for standing-pilot furnaces. … Electronic flame sensors are much less universal, and you must find the exact part specified for your furnace model.

What does a thermocouple do in a 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.

Where is thermocouple on 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.

Do plumbers fix water heaters?

When it comes to hot water coming out of your faucets and showers among other systems, plumbers are the best professionals to call for the job. … In an electric water heater, the most common request for water heater repair can include: Blown fuse. Thermostat.

How much does a furnace cost for a 1500 square foot house?

For example, a 700- to 1,500-square-foot home will require a BTU rating between 40,000 and 60,000, which will cost between $2,000 and $3,000. A furnace for a home ranging in size from 2,000 and 5,000 square feet will need between 125,000 and 150,000 BTUs and will cost in the neighborhood of $3,300 to $6,500.

How do I know if my flame sensor is bad?

1. Switch off the power to your furnace.
2. Close the gas valve.
3. Take out the mounting screw.
4. Carefully pull out the sensor.
5. Inspect the sensor: if the insulation is intact but appears sooty, burnt or slightly corroded, it might only require cleaning.

Can you bypass thermocouple on furnace?

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.

How does a thermocouple work on 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.

Do I need to turn gas off if pilot light goes out?

Since the thermocouple regulates gas going to the pilot, it should cut off on its own if the pilot ever goes out, but that’s only if it’s functioning correctly. If the thermocouple isn’t working properly, then it’s possible that it’s allowing gas to leak into the very room where the heater is located.

Does the pilot light always stay on?

A pilot light means heat, and it also means fuel usage. That flame doesn’t stay ignited by magic – it needs gas. Which means as long as that light is on, you’re using your fuel supply to maintain it.

What do you do when your pilot light goes out?

Your pilot light relies on your natural gas to stay aflame, so if your gas is shut off, your pilot light will go out. Simply turn your gas back on and either relight your pilot light yourself or call a professional.