What's the latest, Timmie?

jim sokolovic

on the gas boiler with integral draft hood. I'm still perplexed about the critical aspects of the draft readings. In your original post, that I just reviewed, you said "the chimney draft was -.02", and the draft at the burners slightly less than that". What is so wrong with these readings? What is your proposed fix - alter the draft hood (which is designed to work properly under these conditions) or alter the chimney (which seems to be within correct specifications for this appliance)? I don't work in the field on gas, but this is of great interest to me! p.s. - please read ASHRAE 103 Boiler Testing Standard for definitions of "flue" and "stack".

Unknown

Jim I do not have

a copy of Ashrae 103 but remember I am not an engineer and do not try to be one. Flue, stack I think in my post a gave information about those terms.

If you will bring up Problem on "CO again" post and scan down to "Todays Results" that will give you what is being done with this job to keep it running. It is not yet complete as I am awaiting the Gas Company to come up with a solution. They will not accept mine and can not seem to find anyone in their midst who knows the answer. They suggest replacing the boiler.

jim sokolovic

I know how some feel about \"Engineers\"...

My dad was an oil burner serviceman for over 40 years, and I heard a lot of grumbling about how the Engineers who designed boilers didn't know anything, every day that I worked with him. I don't qualify myself as an Engineer, but as a Technician. I have more soot in my lungs than brain cells in my head. You presented a field problem that I have taken an extreme interest in, and am trying to understand the details better. I can't imagine why the Boiler Testing Standard wouldn't interest you, at least in the sections that specify combustion reading measurements and proper terminology for the components of heating equipment.

Unknown

I do not feel any way or the other

about engineers, I just stated that am not one. I do not have all of the different manuals and standards for every thing that is out there. I am not sure what this problem about flue and stack is all about. Please give me the definitions from the Ashrae 103. I am sure it is just a misunderstanding of terms. I am pretty sure I am testing in the places I am supposed to and as far as terms I may have used them improperly if so I apologize to everyone who I have confused here.

jim sokolovic

ASHRAE definitions...

Flue: a conduit between the flue outlet of the boiler and the integral draft diverter, draft hood, barmetric draft regulator, vent terminal, or any other point of draft relief.

Stack: the portion of the exhaust system downstream of the draft diverter, draft hood, or barometric draft regulator.

Thanks for bearing with this discussion. I know that I beat it to death, but I thought it was important. I know you want to teach, and of course you are taking the readings the right way - but if the terms are not clear, then someone else that is learning from this may not take the readings the right way.
I reviewed some tests that I did on one of our integral draft hood products last year: -.025" draft in the stack produced very normal combustion results (8.0 % CO2, 10 ppm CO). As I posted last week, tests are run over a wide range of draft conditions. I am starting to picture how excessive draft could actually impede the flue gasses from exiting the boiler, as you described, but have never experienced it myself or heard of this before. If this is the problem, I can see the difficulty in getting it resolved. How do you address this in your classes?
Respectfully, Jim

Unknown

One of the things I

emphasis in my classes is to think beyond what you know and to use some imagination when it comes to difficult problems. Then revert to the techniques you know and are comfortable with but always be ready to see something you have never seen before. Then you have to think like water, steam, air, pressure, electricity, flue gases etc.

The problem with draft hoods is that fixed opening on them (not adjustable) does not work in every sistuation. The volume of dilution air tends to cool the flue gases to much and literally acts like a barrier to good drafting or in some cases excess draft.. With atmospheric gas conversion burners installed into the old coal boilers this was often a problem. We would therefore cut in neutral pressure point adjusters into the draft hood. That way we could adjust draft. I prefer barometrics on power gas conversion burners as you have flexibility to adjust them. In 1967 I began to experiement with problem jobs on designed furnaces and boilers and discovered that if I partially or fully covered the draft hood it made a big difference in the combustion analysis. Then with my imagination working I decided to try a barometric on first an atmospheric gas conversion burner. By the way we had a rule back then that you could not use a barometric with an atmospheric burner because of the need for high excess air. That was the reason oil burners were always more efficient than gas, oil power burners needed less excess air. Much to my amazement I found that the combustion analysis was improved (keep in mind we tested back then with Fyrite bottles so it was a lot of trial and error).

I began to continue my combustion study on design gas equipment. It was almost always the case that when I sealed the draft hood and replaced it with a barometric that the carbon monoxide went down and my combustion efficiency increased. We did a few of these in employees homes and their gas bills decreased sometimes 25 to 35% from before the adjustments.

When electronic testing came around it was like a new world for me with testing and finding what equipment could do. I even began to test ovens, dryers, space heaters etc. It was a real eye opener as to some very high Carbon Monoxide readings on some of this equipment.

Here is the final deal on all of these tests and changes. We always had to put them back to original factory design conditions per company policy. I have never really had a definite factory approval on any of the testing we did. They would get real nervous when you talked about it.

I because of the type of training I do have to go by the rules but I sure do wish everyone would wake up and step outside the norm and see what happens.

Mark Hunt

Timmie


Would you happen to know what the level of training "factory" people go through?

Are they always the best folks to get advice from?

Not trying to start an argument, I sincerely would like to know.

Also, do you know of any installation instruction manual provided by a manufacturer that mentions combustion testing on gas fired equipment?

Do any of these manuals give "acceptable" CO levels?

I have never found any, but maybe you know of some.

Thanks!

Mark H

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Unknown

Mark, the answer is

that in my years of experience I have found factory people run the gamut of well trained and very knowlegeable to knowing nothing and calling them is a waste of time. Thankfully they are few and far between. We are blessed to have some excellent factory folks here on the Wall who are a real asset. I have had very good experience with most over the years. It is also important to know who to talk to. My personal experience is that 90% of the control companies and equipment companies have been very good with me over the years. There are some who over the years I took under my wing and helped them to know how to get along with trades people who sometimes yell and swear a lot,it is never personal. I would always tell them, listen to what they say between the swear words and you will be able to tell what their problem is.

When it comes to combustion that is often a different story. Part of that is because combustion is something you have to learn, in addition to any formal training, in the field. Some factory folks do not get into the field that much if ever.

Years ago when the factory met you on the job they rolled up their sleeves and got into the problem with you.

I once worked with a Japanese company on an equipment problem. They flew their expert over from Japan. He went up on the roof with us and from memory began to go through that equipment item by item wire by wire. He had a tape recorder with him and contioussly talked into it (often in Japanese) when he was done he turned to us and said. Get some lights so we can finish this tonight. He then confered with his home office. Upon completion of that he began to take the unit apart, after about an hour he jumped with excitement and said Ah ha I have found the problem. We replace this and I buy everyone dinner. He was a pro of the highest caliber. I spent the next two years every time I could picking his brain.

Of the top of my head manuals that mention combustion testing are few. There are some that come to mind such as the Trianco Heatmaker and I know there are others and if not specifically they mention the need for setting up equipment properly in the field. Some of the newer equipment mentions CO2 and O2 readings you should expect. I do not have all the names in my head but it is probably a good thing to research.