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.
What does it mean if your pilot light keeps going out?
The most common reason that your pilot light on your water heater keeps going out is a damaged, bent or dirty thermocouple.
How do I stop the wind from blowing out my pilot light?
You should hold down on the pilot light for at least five seconds once it is lit before letting go. This will ensure your pilot light won’t blow out right after you light it.
How do you know if you have 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.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.
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.
How much does it cost to fix 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 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.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.
Why does my furnace flame keeps going out?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.
Article first time published onCan 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 causes a thermocouple to go bad?
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. … If thermocouples start to give out unusual readings, it may be suffering from metal fatigue.
How much does it cost to replace a pilot light?
Pilot light out (gas): $45-$150 per hour for repairs. As with conventional gas systems, plumbers find that the pilot light is one of the most frequent culprits.
Why does my ventless 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.
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.)
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.
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.
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.
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 do thermocouples do?
Thermocouples are sensors used to measure temperature. … A thermocouple consists of two wires, or wire legs, made from different metals. The legs are welded together at one end, into a junction, where the temperature is measured. A voltage is created when the junction senses a change in temperature.
Can you bypass thermocouple on furnace?
To bypass the thermocouple: Move the tilts switch wire aside. Remove your thermocouple from the heater using an 8mm wrench. Pull the valve housing aside using your 13mm socket wrench.
How much should a 50 gallon water heater cost installed?
How much does it cost to replace a 50-gallon water heater? A 50-gallon water heater costs around $1,000 for an electric heater and $1,200 for a natural gas heater of the same capacity.
How many years does a water heater last?
It would be nice to know when the time is right to replace your water before it springs a leak and causes an inconvenience or worse yet, damage to your home. Typically a residential hot water heater lasts between 6 and 13 years. Beyond 12 years, you are on borrowed time!