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high Co2 readings, wet tester

rockhound57rockhound57 Member Posts: 14
I just replaced the fluid in a new to me Bach. wet kit, first boiler tested in normal range, next was combination wood/oil furnace, couldn't get Co2 above 8%, figured due to combo setup (later it was recommended to install low firing baffle). Now the main point: tested pair of W/M SGO9 steam boilers with Riello F10 burners, closed air to trace smoke, then backed out to start fine tuning. CO2 started at 18.5%, then after opening air .4 beyond recommended setting (.6 beyond trace smoke), it was still reading 17.5+ %. Anyone seen this or got a clue? Although I've worked on systems for 10 years plus, it was mostly assisting the company heat tech on install/ swaps or emergency work (my department was plumbing primarily) I've been to NEFI and NORA Silver, comfortable with most aspects, just never had much opportunity to practice  cleanings and testing until I got layed off, now i'm jumping in with both feet. Thanks


  • billtwocasebilltwocase Member Posts: 2,385
    wet kit

    is the scale zero'd out? after the test, be sure to depress the top a few times to get all the fluid back down. Make sure the adjustable scale starts at zero, and that it can be-overfilling the tester will not allow you to adjust to zero. Digital is the way to go, but I give credit where credit is due that you are testing combustion with what you have on hand. I have Testo and still have some old wet kits. They get the same results, but the wet kit doesn't give you print outs and co test. Both are important. Good luck
  • rockhound57rockhound57 Member Posts: 14

    thanks, B2C, yes, I have zeroed it, and check each time I take it out.  
  • icesailoricesailor Member Posts: 7,265
    High Co2 Readings:

    I recently noticed something like this. I think it may be something like this.

    They were W/M WGO boilers. They were not cold start. They were warm starts. They were extremely clean after running for over a year since last cleaning. There was no black soot in the boiler, just a brown ash. I thoroughly cleaned these boilers. Opening the front and cleaning out inside. All had Carlin EZ-1 burners. I never leave them at over 12% Co2. Anymore and I may get soot later. So, I know what they are at. They are running low or ultra low sulphur fuel. After cleaning, I got 18%. Two more tests gave me slightly lower. No smoke, so I left them where I usually did. Went home and cleaned my own WTGO. 15%+ after cleaning. Cleaned and rebuilt my Bachrach with new gaskets and fluid. Same exact results. Am told numerous times that #2 healing oil can never go over 15.5%. I accept that.

    I think that the brown ash has a unburned carbon element to it and after cleaning, will at first give you a higher [email protected] reading. After running for a while, it probably goes back to normal.

    Just a thought of mine about it. It is as plausable as anything else I can come up with.
  • icesailoricesailor Member Posts: 7,265
    High [email protected] readings:


    They run even better on Low Sulpher (LS) or Ultra Low Sulpher (ULS) oil.

    I've cleaned warm start boilers running on the above fuels where I almost felt guilty in cleaning them and changing oil filters.

    But rewarding though.
  • rockhound57rockhound57 Member Posts: 14
    thanks, but.....

    Noone I've talked to yet has been able to explain why I got 18% readings, would anyone have any other suggestions? Thanks for the comments so far.
  • icesailoricesailor Member Posts: 7,265
    High C02 readings:


    Have them come back and test it now that things have settled down. I'll bet that they aren't 18% now. If they aren't, it proves what we/I said.

    If they are still high, ask a guy on another oil burner site. He won't believe it. Then, ask Bachrach about it. Or Worrel or Testo. I'd like to lnow why. I've seen it too.
  • rockhound57rockhound57 Member Posts: 14
    edited November 2010
    mybach's first answer

    From: [email protected]>

    To: "------------------"

    Subject: FW: Feedback Form

    Date: Tue, 16 Nov 2010 09:22:31 -0500

    Tom, it sounds like on the third boiler that there's not enough oxygen to support the combustion process. With CO2 that high that tells me that the oxygen is very low

    Thank you,

    Not very helpful
  • icesailoricesailor Member Posts: 7,265
    High Co2 readings:


    Interesting point, but, in my experience, whenever I had Co2 readings that high, I had smoke because of imcomplete combustion/lack or air/oxygen. When I have found these high levels on equipment I normally service, I have no smoke, and I close the air shutter down slightly, and immediately start showing soot on my instrument. Going back to the old setting, the one I was at when I started, shows no smoke. If I clip my ohm meter to the FF terminals, I see the difference. If I start adding more air, the draft over the fire goes up and the resistance # goes up. Same as when I get smoke.

    What is interesting is that "others" have seen this. Not everyone does combustion testing.
  • Jean-David BeyerJean-David Beyer Member Posts: 2,665
    Not everyone does combustion testing.

    Why not? Doctors have stethoscopes, thermometers, and blood-pressure testers. Why would heating professionals not have combustion analyzers?
  • icesailoricesailor Member Posts: 7,265


    I can see that you just do not understand.

    They are smart and we are not.

    They have been looking at flames for so long, they can adjust them in their sleep. Me? 40+ years and I STILL don't know what I'm looking at. I even have to use a ohm meter to pick up the really subtle changes in flame color because I wasn't born with Superman eyes.

    I don't see smoke in the flame unless it is coming out the chimney so I must use this thingy where I put a piece of paper in this tube that looks like the pump I use to pump up my bicycle tires and pull it 9 times. Just to see if it is black.

    Oh well, you know the drill. They are smart, and we are not. I accepted that a long time ago.
  • Jean-David BeyerJean-David Beyer Member Posts: 2,665
    They are smart and we are not.

    I do not know that I agree with that. Even doctors complain that they do not spend enough time doctoring, and too much time fighting with insurance companies.

    There was a joke going around a coupla years ago like this:

    A doctor had a plumbing problem and called in a plumber. The plumber fixed it in a few minutes and submitted a bill for $500. The doctor complained that that was too much for 15 minutes work. He said, "I am a doctor and even I do not make that much money." To which the plumber replied, "I did not either, when I was a doctor."

    I think those in "the trades" who are good at their work and know what they are doing should not be looked down upon. It is my impression that they are not in the majority, to my dismay. But that is probably true in the medical profession as well. If it were not, perhaps malpractice insurance would not cost so much.

    Do not accept "They are smart and we are not." At least to yourself. Just imagine what a heating system would look like after a doctor worked on it.

    Sign in my former car dealer's show room:

    We made a deal with the bank.

    They do not sell cars.

    We do not give credit.
  • icesailoricesailor Member Posts: 7,265
    They're Smart:


    You may have missed my dry sense of humor in writing. I have a electrician friend who uses that expression to cover such things as the unanswerable questions.

    It isn't that some of us don't know what we are doing, it is that some of us are overwhelmed and perplexed at what some do that we have to go against.

    I'm sure that you, like me have in your time seen a really impressive fluster kluck done and the only comment could be "Oh My God!!". Well, the only way to reconcile that is to say, "They're smart, and we're not". They must know something that we don't know. Or like I said to someone once who had this great idea for something simple but had plans. "you know, that might work for you. I've never seen it work for anyone else but it might work for you." If they want to do it like that, go to it.

    As far as doctors go, I told one, a friend and customer, "We use the same process of elimination, diagnosis and treatment. The only difference between us in the treatment is that I can go to the supply huse and pick up what I need to fix your problem. You don't have a supply house to go to and do a trial and error scenario if needed."

    If a doctor screws uo, someone may die. If we screw up, we may not get pain or asked back. But no one dies. 
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