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Carbon Monoxide Question

Dale Member Posts: 1,317
I think the first year was 1946 and the number of CO deaths from heating equipment has dropped every year since. Certainly auto CO has decreased from over 100k at idle all the time to 30 k cold and much less when the cat converter has warmed up, how many CO deaths have you heard of from direct vent equipment? Even with 50 million more people since '46.


  • Is the CO problem getting worse

    or has it improved over the last 60 years? Let us hear from everyone on this. The question includes pipeline gas, motor vehicles and other sources.
  • Bruce_6
    Bruce_6 Member Posts: 67
    don't know

    if it's getting worse or better.......

    in the area where I am at, there are two companies that check anything. all the rest just put it in, adjust a few screws and leave.

    I showed my boss the testo, and he had never seen nor heard about this kind of instrument. he said he has been plumbing for 45 years, and NEVER tested anything! didn't know he should be testing.

    I think the literature you guys are putting together, should be geared toward both the consumer, but more importantly, the contractors, or installers, and repair people. maybe they need to be certified BEFORE they are issued a license, or certified before they can get their license renewed! that would certainly raise the awareness of everyone!

    actually my boss is now enthusiastic about getting some testing equipment. and might be willing to spring for some training.

    Its gonna take a lot of effort to make things happen!

  • Steamhead
    Steamhead Member Posts: 16,242
    Maybe getting better

    I hooked up a brand-new KitchenAid stove today- first time I've seen a new stove that I didn't have to re-adjust so it wouldn't produce lots of CO. Maybe things in that area are improving.....

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  • Greg Swob
    Greg Swob Member Posts: 167
    I was told

    that it was unnecessary to test for CO and that I am more or less wasting time by doing so. "A nice blue flame is what you look for and that is the best indicator of no problem". I still test flue gases and at supply duct difffusors for CO - during fall pre season system checks & other service calls. I do not have a true combustion analyzer, but do have a CGI tester with CO & O2 sensors and a flue test adapter. Historically, CO deaths are on the decline, but still do happen. I feel consumers are far more cognizant of CO dangers than ever before are not bashful about calling in suspecting CO. Also, we are finding a lot more homes equipped with CO detection than before. Greg
  • Mad Dog
    Mad Dog Member Posts: 2,595
    Greg, whoever told you that needs Jim Davis' class NOW!

    Atleast you are testing with something, but you really need to invest in a nice unit by Bacharach or testo.. ilove the Bacharch so much I bought 2. Once you start testing, it is contagious. You can charge good $$$ too. Go to the next nci class and become your areas CO Expert. Mad Dog

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  • A Blue Flame does not indicate a lack of

    Carbon Monoxide. In fact you could have a good CO2 reading of 8% or even 10% and be making CO.

    We are running a Combustion Testing class on Feb 12, 2004 at our center in Warren, RI. It is imperitive that testing be done, from that point correct adjustments need to be made to equipment.
  • From 1939 to 1998

    Total CO deaths are on the decline. Total CO deaths peaked in 1945, as did pipeline gas deaths. Pipeline related deaths were the major fraction of total deaths until 1959. when they were surpassed by vehicle deaths, which remains the major cause of accidental CO deaths. They continued to rise until 1980 when automobile related Co deaths began to decline. The number of deaths in 1945 was over 1,800 for 1995 it was 460. CO deaths are declining at a rate of 5% per year. This is a clear indication that the problem is diminishing.

    There is however an increase in the number of serious illnesses related to CO. The CPSC estimates about 10,000 persons per year require hospitalization or emergency treatment for CO poisoning.

    The most dangerous place for CO is the residental home.

    Every time you are in a customers home testing should be done. If we do that the numbers will keep coming down.
  • Mark Hunt
    Mark Hunt Member Posts: 4,909
    CO deaths

    I would have to say that the number of deaths is declining, BUT I am wary of any statistic regarding CO deaths.

    CO will come out of a body in about 24 hrs and unless a coroner is looking for it, they will not find it.

    I wonder how many "natural causes" deaths are actually misdiagnosed CO deaths?

    And what about SIDS? Could CO be involved there as well?

    The medical community can miss this stuff just as easy as anyone.

    The equipment that is available today will make people safer, but not every contractor uses good equipment or follows safe installation practices. How many unvented gas water heaters have you seen out there? I've seen quite a few.

    Mark H

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  • Mark, those statisitics

    are based on proven incidents that definitely had CO as the cause of death. You are right because less than 1% of deaths in USA ever have an autopsy done. So I am sure many CO deaths slip by the statistics.

    The greater concern to me is the increase in illness attributred to CO.

    I have read a recent study in the New England Journal of medicine about SIDs it mentions at several points in the article the possibility of airborne disorders (CO is one that is listed as possible contributors to the end result which is SIDS) there are however many other possible causes and their findings are incomplete.

    Unvented water heaters are just about a thing of the past here in RI. With the gas company being the inspecting agency for installations and strictly following code we do not have many installation problems. The biggest problem is DIY'ers and hackers who slip under the radar many times. I would like to see a law that requires the producing of a liscence and permit before you can purchase heating and water heating equipment.
  • Greg Swob
    Greg Swob Member Posts: 167
    We're working on the purstring holders to

    let us order an analyzer and a couple of bore scopes. I've borrowed a scope and like the ability to see deeply in furnace HX's! If it were not for this site and the wonderful/helpful Wallies, I probably wouldn't test for CO. Thanks to you all for all you do for me. Greg
  • Kal Row
    Kal Row Member Posts: 1,520
    as an nyc certified emmissons specialist...

    i give you a few rules that people forget again and again.

    perfect combustion of HC ie a hydrocarbon (gas,oil,etc) produces
    water and co2 and whatever non hydrocarbon junk was in the fuel like sulfur into sulfur-dioxide - and if it's hot enough, it also burns the oxygen and nitrogen in the air into nx or oxides of nitrogen,

    now if the mixture is rich - ie not enough air (O2) to go around for all the hydrogens and carbons, then you get a little water and co (carbon-monoxide) a instead of co2 (carbon-dioxide) and if you really dont have enough air, you get "C" pure carbon (soot), and co, and hc (unburnt hydrocarbon)

    if the mixture is to lean (too much air) you DONT, i repeat DONT get CO!!, but you do get lots of hc (unburnt fuel) and o2 (yes real unused oxygen in the exhaust, which in a car, the catalytic converter uses to burn the left over hc at a lower temperature)

    so a deep blue flame may indicate the hottest mixture - but not necessarily no co, you need to cut the air down past the hottest point to the lean side to guarantee that no co is produced - indeed in cars the mixture is leaned so you dont get detonation when the spark goes off way before the piston reaches the top since the fuel and air particles are more spread out, the flame front travels more slowly from molecule to molecule until it's in full combustion at the top, i am a pilot of light piston aircraft and i always lean the engine until it's at least 50 degrees cooler than peak ie lean of peak which gives the engine the longest life, to go richer than that, you would have richen up the mixture until the exhaust temp reads 100 degree lower or rich of peak, in order to get the mixture rich enough to cool off the cylinders to a point, that offsets the heat created by the faster burning rich mixture, of course rich of peak is a huge waste since it produces co and less energy per gallon, as opposed to 50 degree lean of peak (ie lean until the engine is 50 degrees cooler than max) which give you a 99% complete burn, and a far softer flame front

    this is another reason why it so important to use primary/secondary/closely spaced tee injection, since with a lean mixture, you really need the keep the boiler above 140 degrees so the you dont get a lean miss, ie heat+air+fuel not connecting!!!

    it's mind boggling that, these simple sociometry rules are lost on many engineers, mechanics, and manufactures alike
  • jim sokolovic
    jim sokolovic Member Posts: 439
    Nice dose of irrelavent information...

    Mr. "Expert" - in our field, CO formation due to impingement of a LEAN flame on the heat exchanger can be as high as that caused by an overly rich flame. Thanks for the perfect example of ignorance by so-called professionals, though.
  • Mad Dog
    Mad Dog Member Posts: 2,595
    Wow!!!! This is going to be a good fight here........

    wait till Jim Davis shows up...........Mad Dog

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  • Kal Row
    Kal Row Member Posts: 1,520
    only if ...

    the temperature at the impingement point's cool enough to make the mixture effectively rich, rules of physics dont change, you need to know exactly whats happening at the flame front, "be the flame..." - i did say that you have to run the boiler hot or at the cold spots you get a lean miss equivalent to a rich mixture - you will have spots with to much air not enough fuel, too much fuel and not enough air,

    i know a mechanic that passed cars by sticking the inspection probe into an exhaust hole of his forced air system and never get co if the unit was warm no mater how lean the air was set - i am real sceptical if a hot water gas boiler above 140 degrees produces co, maybe oil sine atomization is harder to control but not gas, i would have to see it first hand to believe it
  • Dale
    Dale Member Posts: 1,317
    Heat exchanger testing

    If you want to learn how to inspect warm air furnace heat exchangers you should take a class from the very opinated and passionate Ellis Prach of www.heatexchangerexperts.com He's from the Denver area so ME probably has an opinion of his techniques. Ellis has a picture book of most furnace brands and where to look for cracks,updated yearly for a small fee. his inspection mirror design is the best I've seen. Sadly when I took a class from him most of the people there were home inspectors. I AM NOT saying that just cracks are a deadly CO risk but looking for them before you replace a direct drive blower motor will save you alot of embarassment.
  • I've seen it

    I believe it. Co can happen with a lean fire with too much secondary air.

    Underfired heat exchangers are worse than ones fired at rating.

    If you haven't tested, you don't know.

  • Dale
    Dale Member Posts: 1,317
    CO risks

    A couple of things to consider, a New Mexico study found almost 50 percent of deaths by CO also had a high blood alcohol level. Not hard to figure, people do stupid things when drunk, a fire dept friend says most Sat. nites they have the pizza on fire fire where the partyer turned on the oven and passed out, sometimes not taking the pizza out of the box or removing the plastic. passing out in running cars not so smart also. Then there's the Men vs Women CO death rate, 15 to one men in the lead. Why, outdoor stuff in campers, cabins, ice shacks, and the obove reason and the working on cars reason. CO deaths are not a bell shaped curve of the population.
  • Kal Row
    Kal Row Member Posts: 1,520

    you disaggree with setting the air with a gas analyzer until the co is lowest, at the design operating temprature in a cast unit? and is a 4 gas analyzer not up to the task?
  • jim sokolovic
    jim sokolovic Member Posts: 439
    Better interaction happening now...

    Sorry to jump on you in the last reply, but it was alarming the way you stated the "no CO possible with a lean flame" thing so boldly. I too, will have to see for myself if only a cold heat exchanger + impingement = CO (on a gas boiler). But keep in mind all of the condensing, low temp and cold start boilers out there. Even if you are correct, how do you propose preventing CO with your recommended lean flame in these cases? Also keep in mind the other effects of leaning the flame beyond the manufacturer's specified air/fuel ratio (CO2) - loss of efficiency, reduction in flame signal, possible ignition problems, rumbling, etc.
  • jim sokolovic
    jim sokolovic Member Posts: 439
    Burner air/fuel ratio setpoint...

    Should not necessarily be at where the lowest CO is found. It should be midway between where richening or leaning causes the CO to rise. This gives the best assurance of being as far from the CO formation points in either direction. Whether it's due to poor mixing, not enough air, or approaching impingement, CO flies up to extreme levels at these points. I have seen zero CO or close to it, just before further leaning creates 600 ppm CO or worse, in many cases. I'll take 30 ppm CO, with tolerance for change in the CO2, any day.
  • Kal Row
    Kal Row Member Posts: 1,520
    the problem is...

    that there are way too many factors...
    do you set it for the lowest co?, if not how much co
    is acceptable? and has anyone built a unit with
    test ports all over the sections to get localized effects,
    only a jet-engine design/test lab has the tools for this,
    ya think GE will just let slant-fin use it for a while? ;)

    and wait, now comes the new nx emission standards, you'll see o2 sensors and catalytic converters - just leave it to the EPA types to make us crazy - IMHO just a tad lean of peak and a good tight flue with a good draft and NFPA recommended fresh air supply is all you should need - before we get all crazy for nothing and i literally mean for "nothing" since no one is going to pay us for this nonsense if their co detector is not going off

    this is why i am a big fan of sealed combustion, and where i cant have sealed combustion i put in a ducted outside fresh air fan driven by a relay off the ig-module input just to be sure - there so many sealed boiler rooms in the middle of the house out there and the owners wonder how black stuff comes out of natual gas, i have to give them a hydro-carbon chemistry lesson - physics bites
  • Kal Row
    Kal Row Member Posts: 1,520
    fair enough - i can live with that

  • Keep it simple gents

    the more complex we make this CO thing the less us service types will shy away from testing.

    Let me give you an example of what the old timers had to deal with before electronic testing. We had to be combustion oriented by being able to look at a flame, after determining the input was correct (over or under firing are both problems), insuring that the venting was correct, do we have sufficient air for combustion, cleaning the boiler or furnace (should be done once a year), firing the boiler or furnace and because we had no electronic testers or draft gauges we used a match at the draft hood to insure some kind of draft (could be excessive or not enough, then look at the flame is it lifting, is it floating what is happening in the combustion chamber after the unit is running for 15 minutes or so. Put your hand on the flue pipe, spit on the pipe will sizzle off at 600 degrees or higher (nasty but at least no high stack) stick your hand into the flue and see how wet the flue gas is. If you do this enough you get real good at it. Keep checking the flame, smell the flue gases (you get to know what good combustion smells like). Go up on the roof if possible and smell the flue gases coming out of the chimney, wet a finger and rub the masonry if it is salty to the taste you have a condensing problem on the chimney. Back down to the basement, your Fyrite bottles should be just about at room temperature (never set them on the boiler or furnace). Drill a hole in the flue before the diverter or barometric, on some units you have to go in thorough the diverter to get a good reading. Take both a CO2 and O2 reading along with temperature of the flue gases ( I drill two holes so I can moniter the flue gas temperature) testing should be done with all doors in place and the house as tight as it can get with all the exhaust fans in the house running and the dryer. If that sucker will give you a good CO2 and O2 reading with stack temperature well above dew point (over 300 degrees today they talk 275 degrees) (theoretical dew point 140). The last thing we would do is use our monoxor colored ampoule type tester using different levels of squeezing 1 squeeze then 3 then five and then 10 if it changed color at all we started all over again. When you have done it that way in the real world of customers basements you get pretty good at too lean or to rich. When electronic testers came around I thought I had died and gone to heaven.

    Back in those days we tested heat exchangers with spirit of peppermint in pill capsules (two man job) one guy put peppermint on burners the other guy had to stay up stairs to see if he smelled peppermint when the furnace came on. If he did we shut them off and a new HX'r was put in or a new furnace. We probably changed some that did not need changed but better safe than sorry.
  • Dale
    Dale Member Posts: 1,317
    Simple indeed

    For CO deaths anyway. The problem isn't usually something too hard to see, vent pipe missing, chimney blocked, cars running in attached garage, black soot on gas units. No combustion air source. Just making sure the vent pipe connects to the sky would solve alot of problems.
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