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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 you test a thermocouple?
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. Many multimeters also indicate continuity with an audio alert.
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.
What happens when your thermocouple goes bad?
Normally when the thermocouple malfunctions or isn’t working, it simply shuts off the gas to your heater. This is important, particularly if the pilot light is out, because it prevents harmful gas from leaking into your home.
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.
Should thermocouple be in pilot flame?
The pilot flame should touch the thermocouple at a specific level. If the flame is blue and weak, and barely reaches the thermocouple, it needs to be stronger. If it extends well above the thermocouple, it’s too strong. Install a new thermocouple by screwing it in, heating it up a bit, and then lighting the pilot.
How do you bypass a thermocouple?
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. Remove the valve using your pliers. Put your thermocouple back into position.
How long should thermocouple 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.
Why is my thermocouple not working?
If the appliance has a thermocouple, the problem may be a faulty thermocouple. The thermocouple, which operates as a safety device, turns the gas supply off when the pilot light goes out. When a thermocouple fails, the pilot light won’t stay lighted. A burned out or broken thermocouple should be replaced.
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.
Why will my gas logs not stay lit?
The thermocouple and thermopile are the two most common reasons why a gas fireplace won’t stay lit. However, there are other possibilities out there. Another common culprit is incorrect gas pressure. As the seasons pass, you may find that your gas pressure drops below where it needs to be.
How much is thermocouple replace?
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 you clean a dirty 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 a thermocouple be bad if the pilot stays lit?
NO. The purpose of the thermocouple is shut off all gas flow if the pilot light goes out. The thermocouple is a basic safety feature on anything that uses a pilot light. If the pilot light goes out, the thermocouple will turn off the gas and prevent it from accumulating which can be dangerous or deadly.
How do you test a thermocouple on a furnace?
Remove the thermocouple by unscrewing the copper lead and connection nut (first) and then the bracket nuts. Next, take your meter and set it to ohms. Take the two leads from the meter and touch them—the meter should read zero. Once this check is done, turn the meter back to volts.
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.
Why is my pilot light orange?
If your pilot light’s flame is orange or yellow, it is burning inefficiently due to a lack of oxygen. The thermocouple should sense when this happens because the heat from the flame will not be as hot as it should be.
What color should pilot flame be?
A natural gas flame should be a bright blue color with a small amount of yellow at the very tip. A propane flame will have more of a bluish-green flame with a tinge of yellow at the tip. The flame should strong enough to cover about 1/2 inch at the end of the thermocouple tip.
Why does my pilot light flicker?
Flame flickers or spits – A draft in the room can cause your flame to flicker. Spitting is often caused by a dirty gas orifice or tube. These can be cleaned with a stiff wire, but you’ll need to remove the pilot light assembly to do so.
Does gas go through a thermocouple?
The thermocouple generates a small amount of electrical current when it has been heated by the flame. This small amount of electric current keeps the pilot gas valve open. If the pilot light goes out, the electrical current stops and the gas valve closes. Simply put; no flame, no gas flow.
Why won’t the pilot stay lit on my wall heater?
The Pilot Won’t Stay Lit A pilot that won’t stay lit could be the result of a blockage in the pilot tube. Turn off the gas, clear the tube with compressed air, and relight the pilot. If that doesn’t work, you may need to call a repairman to come and install a new thermocouple.
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.
