Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

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iamblessed
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Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by iamblessed » Wed Dec 18, 2019 7:47 pm

I am working on a Martin Industrries room heater. Pilot light will not stay on flame very weak when holding down Pilot light button. I soaked the Pilot light end in vinegar. I looked like it was dirty. I dried it off and put it back in. I don't know if that was a bad move because now it will not light. As soon as I let up the polit light button it goes out. I put in a new Thermocouple that did not solve the problem. Can I buy the part generic that is the pilot light or do I need only a Martin?
https://i.imgur.com/9I5f7hb.jpg

Here is the part on the right https://i.imgur.com/VqFswtR.jpg
I am handy put do not know all the technical names. Anyone have any other ideas about it being another part?
This has got me stumped.

Housedoc
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by Housedoc » Wed Dec 18, 2019 8:29 pm

May be a gas valve issue. Thermocouple generates millivolts that valve uses to keep gas going to keep pilot lit. If thermocouple good and in flame path, pilot should stay lit.

Topic Author
iamblessed
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by iamblessed » Wed Dec 18, 2019 9:03 pm

Can all these parts be generic or must you use the Brand name parts.

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tooluser
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by tooluser » Wed Dec 18, 2019 9:08 pm

I just had a similar issue with my water heater, but a new thermocouple fixed it.

It's an obvious question these days, but have you gone to Youtube and searched for your heater name, plus the words "pilot won't stay lit"? I have viewed many helpful videos for appliances, air conditioners, etc. It's amazing what's out there. lots of helpful folks have posted videos. Sometimes they are beyond my desired risk level to attempt myself, but then I know what to ask or tell a professional.

sport
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by sport » Wed Dec 18, 2019 9:09 pm

Here is how I solved a similar problem: Look for a small hole in the gas line near the pilot light. I bought a can of compressed air with a thin tube that attached to the sprayer. I blew air into that small hole. This cleared dirt out of the pilot light. The weak flame is a sign of a dirty pilot light.

RetiredAL
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by RetiredAL » Wed Dec 18, 2019 9:22 pm

One of 2 possibilities: The pilot tip is partially plugged hence low flame, or pilot's gas adjustment system and/or the control valve is messed up. The liquid you used aggregated it further. The junk on the pilot tip comes from dirty gas. All gas is dirty. Usually it does not plug anything as the pressure is low, thus large orifice tips. But it can happen.

Some pilot adjustments are a simple adjusting screw similar to a old-style carburetor idle mixture screw, some are of a pressure regulator type. The thermocouple needs a decent flame on it to generate the few hundred millivolts needed to open the gas valve. The pilot light button bypasses the gas valve as long as you have it depressed. If the gas valve has not opened, the pilot goes out when you release the button. Either too little flame, or a weak thermocouple ( they age over many years ) can cause your issue. You can measure thermocouple with a digital volt meter. Since you installed a new thermocouple, that is not likely your ongoing issue.

If you are not gas competent, do not mess with the cleaning/adjustment. You do this at your risk. The pilot tip is cleaned with a very fine wire. Never use a drill bit. The pilot adjust is under a screw plug cover on the control valve. The cover will be marked 'pilot'. The cover may be a gas seal, so don't leave it off. If you disassemble the pilot tubing, do a soap-water leak check. Lastly the control valve has a burner pressure regulator built into it under a different cover. Do not touch. Special tools/gauges are needed. There is a huge difference between house gas pressure and burner gas pressure. Get this wrong, you will have a bonfire.

Control valves are generally pretty generic, mostly having different piping locations. A replacement needs to cross-reference as a replacement to the original. I have not looked, but I would expect U-tube video of all of this are available. Although there are many excellent videos out there on all kinds of subjects, always remember any IDIOT can make and post a video.

HoosierJim
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by HoosierJim » Wed Dec 18, 2019 9:23 pm

The orifice may be plugged or dirty. Get this tool to insure it's clean.

I had this happen on a hot water heater and it turned out the gas regulator on the gas meter was providing an erratic low pressure. Gas company changed the meter and regulator and it fixed the problem.


Topic Author
iamblessed
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by iamblessed » Wed Dec 18, 2019 10:05 pm

Bogle7 wrote:
Wed Dec 18, 2019 9:48 pm
All your answers are here
http://www.early-retirement.org/forums/ ... ost2340603
I figured two forums are better than one.

Topic Author
iamblessed
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by iamblessed » Wed Dec 18, 2019 10:08 pm

Right now even holding the pilot button down I can not get it to light. It has gas because I took it off the pilot to test it. That is what stumps me.

bbqguru
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by bbqguru » Wed Dec 18, 2019 11:01 pm

You can buy a generic pilot assembly-- you will be hard pressed to find a Martin, they're out of business.

What is most likely the problem, since you've replaced the thermocouple, is that the pilot orifice is dirty or plugged.

1.Remove the pilot assembly by taking the thermocouple out of the pilot and then unscrew the pilot tube.
2. There should be an orifice either sitting on top of the pilot tube or up in the pilot assembly. Take a small needle and gingerly clear the orifice out. You should be able to hold it up to a light and see through it. Be extremely careful not to make the orifice hole bigger.
3. Reinstall the pilot tube into the assembly- but be careful as well, it is easy to cross thread.
4. Put the thermocouple back in.
5. Check for leaks at the pilot tube while holding down the pilot button on the valve.
6. Light pilot and make sure it stays lit. If it does, turn it out and install the pilot back onto the burner.

If it won't chances are you need a new pilot assembly.

Topic Author
iamblessed
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by iamblessed » Thu Dec 19, 2019 1:15 pm

bbqguru wrote:
Wed Dec 18, 2019 11:01 pm
You can buy a generic pilot assembly-- you will be hard pressed to find a Martin, they're out of business.

What is most likely the problem, since you've replaced the thermocouple, is that the pilot orifice is dirty or plugged.

1.Remove the pilot assembly by taking the thermocouple out of the pilot and then unscrew the pilot tube.
2. There should be an orifice either sitting on top of the pilot tube or up in the pilot assembly. Take a small needle and gingerly clear the orifice out. You should be able to hold it up to a light and see through it. Be extremely careful not to make the orifice hole bigger.
3. Reinstall the pilot tube into the assembly- but be careful as well, it is easy to cross thread.
4. Put the thermocouple back in.
5. Check for leaks at the pilot tube while holding down the pilot button on the valve.
6. Light pilot and make sure it stays lit. If it does, turn it out and install the pilot back onto the burner.

If it won't chances are you need a new pilot assembly.
I tried canned air on it. It did not work. I will try the needle again. Man is that hole small you can hardly work on it. I almost can't see it.

123
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by 123 » Thu Dec 19, 2019 4:47 pm

Call your local gas utility to come over and relight the pilot. When we replaced a water heater and the pilot on the new water heater wouldn't work properly we called out local gas utility. A guy came out and cleaned the pilot with a gizmo and lite it without a problem. He explained that older gas lines can have residue that can plug pilot lights, if you connect a new appliance to an old line you still can have residue, sometimes immediately. The gas company people look at pilot light issues day after day, they've undoubtedly seen it before. If they can't light it they can likely tell you exactly how to fix it, or advise you that its done for based on the hundreds of similar cases they've seen.

Just call you local gas utility for service
The closest helping hand is at the end of your own arm.

Topic Author
iamblessed
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by iamblessed » Thu Dec 19, 2019 5:42 pm

bbqguru wrote:
Wed Dec 18, 2019 11:01 pm
You can buy a generic pilot assembly-- you will be hard pressed to find a Martin, they're out of business.

What is most likely the problem, since you've replaced the thermocouple, is that the pilot orifice is dirty or plugged.

1.Remove the pilot assembly by taking the thermocouple out of the pilot and then unscrew the pilot tube.
2. There should be an orifice either sitting on top of the pilot tube or up in the pilot assembly. Take a small needle and gingerly clear the orifice out. You should be able to hold it up to a light and see through it. Be extremely careful not to make the orifice hole bigger.
3. Reinstall the pilot tube into the assembly- but be careful as well, it is easy to cross thread.
4. Put the thermocouple back in.
5. Check for leaks at the pilot tube while holding down the pilot button on the valve.
6. Light pilot and make sure it stays lit. If it does, turn it out and install the pilot back onto the burner.

If it won't chances are you need a new pilot assembly.
Update did everything you said even cleaned the old thermocouple and put it back in. I found it very helpful to use a bright flash light on the other end so I could see when the hole was clear. Works like a charm. It had been acting up so long I don't remember how big the pilot light should be. The pilot light just hits the closest part of the thermocouple when it is on is that about right? I noticed the thermocouple wire can get to hot to touch two or three inches from the thermocouple.

Topic Author
iamblessed
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by iamblessed » Thu Dec 19, 2019 7:58 pm

I think the thermocoupler is gettting to hot what do you think?

bbqguru
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by bbqguru » Thu Dec 19, 2019 8:12 pm

Thermocouple won't get too hot. The flame should touch the side and some pilots wrap around the thermocouple a bit as well. As long as it is staying lit, then I wouldn't worry about it.

Topic Author
iamblessed
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by iamblessed » Thu Dec 19, 2019 8:31 pm

bbqguru wrote:
Thu Dec 19, 2019 8:12 pm
Thermocouple won't get too hot. The flame should touch the side and some pilots wrap around the thermocouple a bit as well. As long as it is staying lit, then I wouldn't worry about it.
The only thing that concerned me was the wire in the back of the thermocoupler getting to hot to touch for about 2-3 inches is that normal?

RetiredAL
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by RetiredAL » Thu Dec 19, 2019 9:02 pm

iamblessed wrote:
Thu Dec 19, 2019 8:31 pm
bbqguru wrote:
Thu Dec 19, 2019 8:12 pm
Thermocouple won't get too hot. The flame should touch the side and some pilots wrap around the thermocouple a bit as well. As long as it is staying lit, then I wouldn't worry about it.
The only thing that concerned me was the wire in the back of the thermocoupler getting to hot to touch for about 2-3 inches is that normal?
A millivolt TC has to be hot to work and the wire is designed to handle that.

Topic Author
iamblessed
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Re: Working on a room heater Pilot light will not stay on flame very weak when holding down Pilot light button.Need help

Post by iamblessed » Thu Dec 19, 2019 9:26 pm

A Big Thanks to everyone who helped me fix this. Great folks great forum.

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