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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 gas pilot light keep going out?
Some of the possible serious reasons for pilot lights to go out include loose or broken gas valves, thermocouples or heat exchangers, faulty venting, low gas pressure, or high winds. If you believe there is a serious problem, don’t hesitate to contact a professional.
Why does my pilot light keep going out with a new thermocouple?
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.
Why won’t my pilot light stay lit on my furnace?
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 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.
How do I know if my thermocouple is broken?
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.
How long should a thermocouple last?
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 you fix a gas fire that keeps going out?
Easy DIY Fix: Gas Fireplace Won’t Stay Lit Before You Begin: Is Your Pilot Light Lit Inside Fireplace? The Fix: Pilot Light to Gas Fireplace Won’t Stay Lit. Check Your Thermopile Output with the TH/TP Contacts. Don’t Replace Your Thermopile or Thermocouple Right Away. Cleaning the Thermopile. Re-test the Cleaned Thermopile.
Why does my furnace flame keeps going out?
Your furnace has a limit switch that keeps it from running if the heat exchanger is too hot. Dirty filters, closed or blocked vents and other blockages in airflow are common causes of an overheated furnace. A bad limit switch. The limit switch may be bad and need to be replaced.
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 replace a thermocouple myself?
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. Then detach the thermocouple from the burner and take it with you to the home center or hardware store to ensure you buy the right replacement.
How much does it cost to fix a pilot light?
You can replace the thermocouple yourself for around $20. If you hire a contractor to do the work, it will cost $45 to $150. A contractor fixing the thermocouple and the pilot light will usually be able to replace both in one hour, meaning it will be $45 to $150 for both.
What causes a thermocouple to fail?
METAL FATIGUE Like everything, thermocouples can’t stay new forever. 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.
Can I bypass 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.
What can go wrong with a thermocouple?
Six Common Causes for Thermocouple Temperature Measurement Errors Selecting the Wrong Type of Thermocouple on the Transmitter. Problems Related to the Thermocouple Extension Wire. Inherent Variations in Alloys. Temperature Variations Around the Reference Junction Connection. Thermocouple Grounded at More Than One Location.
How do you clean a thermocouple pilot light?
How to Clean a Pilot Light Cut off the gas to your furnace. Remove the pilot light and thermocouple assembly. Use your pliers or wrench to remove the pilot light and thermocouple from the bracket. Using the wire brush, brush away the carbon buildup and soot from both components.
