- 1 How do you know if you have a bad thermocouple?
- 2 What happens if you have a bad thermocouple?
- 3 Why do thermocouples go bad?
- 4 Will a pilot stay lit with a bad thermocouple?
- 5 How much does it cost to fix a thermocouple?
- 6 Can you bypass a thermocouple on a water heater?
- 7 Can thermocouple be too long?
- 8 How do I know if my thermocouple is good?
- 9 How long does a thermocouple last?
- 10 Can you fix a thermocouple?
- 11 Can you clean a thermocouple?
- 12 Can you replace a thermocouple yourself?
- 13 Can a thermocouple work intermittently?
- 14 Can you overheat a thermocouple?
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.
What happens if you have a bad thermocouple?
This means that if the thermocouple goes bad, there is no way of detecting if the pilot light is burning or not. And when the pilot light goes out, you will not have hot water supply in your plumbing system. To test if the problem is with the thermocouple, try to relight the pilot.
Why do thermocouples 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.
Will a pilot stay lit with a bad thermocouple?
What is a 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 much does it cost to fix a thermocouple?
The thermocouple is an apparatus that senses whether the pilot light is lit and triggers the gas control valve. Repairs typically cost about $150 to have it done professionally, though a new thermocouple itself only costs about $20 on average.
Can you bypass a thermocouple on a water heater?
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.
Can thermocouple be too long?
The length of a thermocouple has no effect on its measurement accuracy or its ability to transfer the signal to the instrument. In other words, thermocouples do not experience “voltage drops” or power loss along its length as a high current power line might possess.
How do I know if my thermocouple is good?
Select the ohms or resistance option on your multimeter. 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.
How long does a thermocouple last?
All things considered, the question remains, “How long should my thermocouple last?” The answer to that question is that it depends on the application. In an ideal environment, that length of time can be indefinite.
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.
Can you clean a thermocouple?
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.
Can you replace a thermocouple yourself?
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. Then unfasten the three nuts that hold the thermocouple and the two gas tubes to the valve.
Can a thermocouple work intermittently?
a safety device that has started to go bad, or has failed permanently. In this client’s case, the thermocouple was initially working intermittently, and then finally failed. This allowed the gas to flow long enough to heat up the thermocouple and generate some electrical current flowing back to the gas valve.
Can you overheat a thermocouple?
Overheating. The welding process can ruin the thermocouple if carried out incorrectly. Overheating the thermocouple with the welding tools can degrade the wire. In addition, the gas and atmosphere near the wire can enter the thermocouple metal, changing its characteristics.