Gas valve-Problem? - Contractor Talk - Professional Construction and Remodeling Forum

A.D. Const · 02-15-2008, 09:54 AM

I have a small residential gas boiler. Problem is that the flame is very minimal. The boiler will fire but the flame looks like s match flame (no preassure or sound to it) What do you think the problem might be. I do have normal pressure at the gas line before the valve. If I disconnect the valve I hear it clicking normally (on and off as I connect and disconnect) but the flame is very minimal. HELP PLEASE

knothole · 02-15-2008, 07:02 PM

Check to pilot orafice and see if it may be starting to stop up...

A.D. Const · 02-15-2008, 07:17 PM

Pilot seems fine, I took it out I even replaced the thermocouple, but the flames just do not fire up. Thanks

mdshunk · 02-15-2008, 07:36 PM

Quote:

Originally Posted by A.D. Const

I do have normal pressure at the gas line before the valve.

What manometer reading did you get?

You clearly have a pressure problem. If the input pressure is good (you really need to check), then you may well have a gas valve issue. Audible clicking is not the only check of a gas valve.

ATS · 02-15-2008, 09:06 PM

A poor, weak flame is a sign of incomplete combustion which always means high carbon monoxide levels. If you don't own the necessary tools of the trade and do not have the knowledge, call in a pro, soon.

A.D. Const · 02-16-2008, 08:32 AM

Come on guys lets be serious, Manometer? "sign of incomplete combustion which always means high carbon monoxide levels"?

Do you mean under the boiler it self everything else is fine

.

Now being serious, The reason I like this site is because a pro can ask pertinent question when he or she needs the input of others, that is what I was trying to do. Is hard to believe someone knows what I have or don't have in my truck or even start questioning my qualifications to do the job.

Pressure is 1-2 Lbs which is normal in a residential application.

ATS · 02-16-2008, 11:21 AM

I for one was being serious. I'm not sure what you were getting at with your last response. A weak flame is usually always accompanied by high CO levels in my experience. 1-2 lbs pressure is NOT normal for a residential boiler. 3.5 " WC is at the manifold is normal. You have to do the basic checks in order to diagnose the problem. What is your input pressure?

A.D. Const · 06-22-2008, 07:21 AM

I forgot to post outcome, I replaced the gas valve and problem solved. Thank you again for your input.

MechAcc · 06-22-2008, 01:08 PM

Now that the valve has been replaced has the burner manifold pressure been rechecked for correct setting? Was a combustion test for O2, CO2 and carbon monoxide levels? Have seen many new valves that are not set at the correct pressure.

22rifle · 06-22-2008, 01:48 PM

Quote:

Originally Posted by MechAcc

Now that the valve has been replaced has the burner manifold pressure been rechecked for correct setting? Was a combustion test for O2, CO2 and carbon monoxide levels? Have seen many new valves that are not set at the correct pressure.

Scary stuff isn't it?

neolitic · 06-22-2008, 02:04 PM

Wish I knew where this guy is.
Have a feeling sooner or later
he's gonna be in the newspapers.

mdshunk · 06-22-2008, 02:06 PM

Quote:

Originally Posted by neolitic

Wish I knew where this guy is.
Have a feeling sooner or later
he's gonna be in the newspapers.

Eh, probably not, but not doing something as simple as a manometer check is just plain dumb. The fella acted like a manometer was some sort of tool from Mars, but every furnace tech probably carries one in the toolkit he initially carries in to start to work on any furnace. I'm just an electrician, but I have one on my truck. Generators, you know. A manometer is to a gasman what a volt meter is to an electrician. Without one, all you can do is guess. It's not even an expensive tool.

neolitic · 06-22-2008, 02:12 PM

That and the part about incomplete
combustion and CO not being such a
big deal...

A.D. Const · 06-24-2008, 06:03 PM

Correction, How do you get pressure without using a manometer? I never said that I did not used a a Manometer, nor did I said incomplete combustion and CO wasn't a big deal. If that was the case I wouldn't need to post any questions would I? I've been in the trade for 25years, and I though someome might have some insight or reccomendation with out being judgemental. I do not claim to know it all, but we have to treat each others with due dignity.

flashheatingand · 06-28-2008, 12:47 PM

For being "just an electrician", you know quite a bit about hvac. Just wanted to acknowlege your smarts

22rifle · 06-28-2008, 02:06 PM

Quote:

Originally Posted by flashheatingand

For being "just an electrician", you know quite a bit about hvac. Just wanted to acknowlege your smarts

Who you talking to?

MDShunk? If so, that's because he is just an all around smart guy. Serious.

neolitic · 06-28-2008, 02:14 PM

If I'm not mistaken, he also has
his HVAC ticket.

A.D. Const · 06-30-2008, 02:47 PM

Yes I will add that on my opinion Mr. Mdshunk, is one of the most knowledgeable and respected individuals in this forum.

flashheatingand · 06-30-2008, 07:01 PM

Quote:

Originally Posted by A.D. Const

Yes I will add that on my opinion Mr. Mdshunk, is one of the most knowledgeable and respected individuals in this forum.

Knowlegeable and respected yes, but I am not too sure about his taste in hats