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CO problem???

I recently had a hot water boiler installed, (oil).

The unit installed and then checked for efficiency by a licensed oil burner tech, and everything checked out fine.

Now the problem, An independent vendor for NSTAR Electric came by to do there inspection and tells us the co level in the flue has maxed out their meter at over 2000ppm. The drafty is ok, it is going up the chimney and there isn't any levels in the occuppied space in the area of the boiler.

My tech says there reading aren't correct and would come out to verify but couldn't make it right away. My wife, being nervous called our oil co. and they sent a tech out to do a test.

He stated that the draft was neg. the co was 9.7 % not ppm ( which he says oil burner aren't read in ppm).

I'm getting mixed information on this and I'm hoping someone could clear this up for me. They are using 2 different testing instruments The tech using a bachrach liquid test and the inspector a digital test instrument.

Sorry for the lenghthy explanation, I look forward to anyone's answers.


  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
    Digital versus Shaker kit.

    THe liquid combustion tester does not check carbon monoxide.

    9.7% sounds more like a CO2 reading, which the liquid tester would have the ability to read.

    You need to get a qualified burner tech in there with a digital combustion analyzer to get it corrected. Having high concentrations of CO in the flue gas stream is potentially dangerous. If there is any back draft condition, or spillage, the CO will invade the home. Get some good CO alarms and place them on each level of the home (except in the boiler room) and when you call the burner techs, ask them if they use electronic digital analyzers that have the ability to test for CO in the flue gas stream, not CO2

    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Iceman01
    Iceman01 Member Posts: 4
    CO problem???

    Thank you for your reply. What range would be acceptable for flue gas? This way I'll have an idea when they test it.
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
    I would defer to the manufacturer of the appliance...

    My personal goal is to get it to burn as clean as possible, with a maximum of 50 ppm AIr Free CO, but I believe the "code acceptable" standard is 200 ppm. That number has roots in the oven industry, where flame impingement on the heat spreader is typical, and it is hard to get the CO down. So, the boiler/furnace industry seems to have adopted their standard.

    I really am not qualified to speak to oil burners tho.

    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • MikeyB
    MikeyB Member Posts: 696

    Iceman, take a look at Bacharach's website and search their "Training Room" this will give you good informantion as well, and as ME has stated check with the manufacturer specs on your equip for what numbers they aer looking for in your flue gas sample
  • Steamhead
    Steamhead Member Posts: 16,736
    edited February 2010
    Federal standards

    IIRC allow 400 PPM in the flue gas stream of a boiler or furnasty, 200 PPM for a water heater, and (gasp) 800 PPM for a kitchen stove!

    These are all way too high.

    Have someone look at that boiler who knows what he's doing. Have you tried the Find a Professional page of this site?
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • Tim McElwain
    Tim McElwain Member Posts: 4,608
    At no time should you have

    an air free reading on boilers, furnaces or water heaters above 100 PPM that is .01%. Zero smoke on oil is not an indicator of no CO and all fossil fuel burning equipment shopld be checked for CO.

    On all other equipment including unvented gas heaters and gas range ovens below 50 PPM in the flue sample or in the case of unvented directly above the heater.
This discussion has been closed.