We have a Weil-weyman hot water furnace and have had 3 thermal couplinks installed in 3 years. Is this a lot?
-
Woodbridge Environmental Tiptophouse.com on Feb 16, 2013If the thermocouple is being changed out that often It can be one of two things that is the issue. 1. incorrect install or proper flame or 2, faulty gas valve. To understand what is going on you need to understand what the thermocouple does. Inside the tiny bulb that the flame is coming into contact with is two dissimilar metals. And connect to them is a wire. When the metal is heated it generates a very tiny voltage which is delivered to the gas valve. Inside the gas valve is a winding of wires that sees this millivolt current and the winding's amplify this current to create a magnet. This magnet in turn holds a tiny metal bar into place that keeps the gas valve in a position that allows the main flame to operate. Should the pilot light go out the voltage is loss thus the tiny metal bar is no longer held into position. This in turn prevents the main gas from coming on filling the boiler or furnace from filling with gas that is not lite from the flame. If the flame is not large enough and is not properly hitting the thermocouple in just the right spot it will not produce this millivolt current. If the thermocouple corrodes from rust or debris it also will not produce current, If the connection to the gas valve corrodes or comes loose where the wire connects to the gas valve, it will not transfer this voltage to the gas valve and it will not hold the rod in place and shut down. If the wiring within the gas valve is faulty or has failed, it may require the maximum amount of voltage only a new thermocouple can produce and not work as a result. My guess it is either a poor pilot, a poor connection where it connects to the gas valve or the gas valve is faulty. I have seen in the past where thermocouple fail, but three times? Not so much. If you determine that the thermocouple pilot light is bright blue with no yellow flame at all. Yellow indicates that the pilot light is not burning properly and the yellow will produce soot that prevents the thermocouple from working as it should. And that the bulb end of this device is clean and not dirty, then remove the wire out of the gas valve and very slightly sand it with very fine sandpaper or emery cloth. Just enough to make is shiny, no more. Put it back in the valve and try lighting the pilot again. If that does not work, then the gas valve is faulty and needs to be replaced. Even if works after putting in a new Thermocouple it will fail again. Sometimes the wiring within the gas valve corrodes just enough that it requires the current only a new thermocouple can provide, As they age they loose some of the ability to produce enough current to hold the gas valve pin into place and the result is what your experiencing. Lastly, My only question would be is, Does the pilot stay lit once you light it again? Or does it go out as soon as you release the gas valve plunger that you push to light the pilot? If it goes out again then everything I said before stands. If not and the pilot stays on for a while only to come back later and its off, then you need to check one more thing. Sometimes down drafts in the chimney can blow the pilot out and make it seem that the thermocouple is faulty. If you do not have a strong bright blue pilot flame that can weather an occasional down draft that can occur, then you need to adjust the flame as that is the cause of your issue.Helpful Reply
-
Related Discussions
How do I get grass out of a phlox bed?
This flower bed is extremely dense with phlox. Last year, I pulled much of the grass out by the roots, but it came back with a vengence this year. We've had a ton of ... See more
Has anyone used a shower liner for curtain backing/liner?
I'm making new curtains in several rooms using cotton calico fabric. I'm trying to find an inexpensive -as possible lol- way to give a little more weight to them and ... See more
How can I remove a magnetic door knocker from a metal door?
The magnet in the knocker has "welded" to the door and seems impossible to remove. I have to paint the door so if the paint is damaged its not a problem.
How to remove rust from exterior door hinges without removing them?
GNATS - How to get rid of them?
Somehow my house and garden got tiny gnats that killed my fuchsia plant and fly everywhere. I have tried ALL the Web recommendations - soap and oil dishes, sand in th... See more
How do I remove hard water deposits from stainless washing machine tub
My new home's washing machine appears to have a rough buildup near the top of the stainless tub. I have run Affresh through the unit but this remains. I don't want to... See more
How do we remove calcium deposits on our patio water fountain
How do we remove calcium deposits from our patio fountain and brick walkway?