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Sickening smell (not gas) from boiler - - hazardous to health?

Somewhat sickening smell similar to, but not gas, wafts through house every time now 3-month old steam boiler runs. Contractor said this is a burning off of coating on Union Steam (reportedly bought out Well-Built) boiler metal (not sure if inside or out) and will take time. Recommended waiting for warm enough weather to stay outside all day and run the boiler above 80 degrees with basement windows open. Still waiting for that day. Meanwhile, when the system goes on, I open back and front doors for about a half hour and have to stay on upper floors. This only helps with the worst of it, and only if I am home and awake! First, is this smell hazardous to health? Second, is this good reasonable advice? Third, do these companies not have an alternative to this significant inconvenience? Why don't they burn this stuff off in high heat prior to installation? Seems absurd. Thanks!


  • ratioratio Member Posts: 2,330
    Manufacturing oils burning off is a real thing, but it's hard to smell what you are smelling over the internets. Three months seems a little long to me, but I don't do boilers all the time, so someone else might have a different opinion of that. There are also a number of other things that could be producing an odor when the boiler fires, with various health implications.

    Have you had the original installer back out to examine the work for any issues? Perhaps hiring a different company for a second set of eyes; particularly if you're sensitive to the smells. Check here to see if a member is near who could take a look at it. In addition, you could post a few pics of the install, from far enough back to see the piping near the boiler. We might get a hint of where to look closer.

  • captaincocaptainco Member Posts: 450
    Remember years ago when starting a boiler with the sections coated with oil. When they started to burn off the Carbon monoxide in the room rose above 100ppm and we ran! If the section are coated with oil they need to be burned off as quick as possible in a well ventilated area.
  • JUGHNEJUGHNE Member Posts: 6,788
    Do you have air vents on your radiators?
  • SteamheadSteamhead Member Posts: 13,766
    If the odor is what I think it is, your chimney may be blocked. Shut the boiler down and get it looked at NOW.
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
    SuperTech1Matthiasdelta TDeniseNickelDave in QCA
  • STEAM DOCTORSTEAM DOCTOR Member Posts: 1,141
    @DeniseNickel .A few days. A week, maybe . Three months, not a chance in the world. All new boilers will smell for a few days or maybe up to a week. Never for 3 months. Something is wrong.
    SuperTech1Matthiaskcoppdelta TDeniseNickelGBart
  • EBEBRATT-EdEBEBRATT-Ed Member Posts: 6,930

    Do you suspect the smell coming from the boiler itself? Or from the air vents on the radiators?
  • DZoroDZoro Member Posts: 1,035
    Was there blue pipe tape or paste used?
  • LeonardLeonard Member Posts: 903
    edited April 2018
    I'm not a heating guy so not knowing any better I put car gasket sealer on some gaskets for a rusty circulator flange. Now when I vent air from my hot water baseboards it stinks of Permatex II. Been that way for 4+ years

    Figured since temps and pressures of car and heating system were about same I could use car cooling system sealants......wrong. No leaks , but vented air stinks

  • delta Tdelta T Member Posts: 809
    edited April 2018
    Do you have any Carbon monoxide detectors in your house? -If not get some now. This could be a very dangerous situation caused by a blocked flue and sending high levels of carbon monoxide into your house.

    It could also be a water quality issue or a boiler cleaner added to the water that is wafting out of your air vents (only if you have a one pipe steam system).

    3 months for the shipping oil to burn off is ridiculous. 3 days? sure. Maybe a week. No more though.

    I am betting it is unfortunately the former. Ask the installer for the numbers from the combustion analysis they did on startup (A real pro will be able to tell you). If they did not do a combustion analysis, insist that they return and perform one. If they refuse, find another professional to come check the boiler for proper combustion. If you have a blocked flue (my bet) a combustion analyzer will show it right away.

    I will say it again, this could be very dangerous. People die from blocked flues, I would strongly recommend not running the boiler until you verify it is safe.
  • the_donutthe_donut Member Posts: 374
    Get it checked out, but we have seen issues with blue ptfe tape/pipe dope causing smell. I would have installer come back, check flue and skim boiler.
  • SteamheadSteamhead Member Posts: 13,766
    @DeniseNickel , any update on this?
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • DeniseNickelDeniseNickel Member Posts: 2
    First, thank you so much to so many responsive, caring folks. I share photos as requested. Carbon dioxide detector has been present and functional. Smell does not come through radiators - just boiler area and seeps through basement, up basement stairs and through floorboards above boiler. Contractor supervisor came back shortly after install - said all good, gas leak test negative. I am unfamiliar with tape, dope or other materials used. Can you tell from photos? After reading comments, I will ask contractor to come back again.

    Thanks sooo much. This is a great site!
  • EBEBRATT-EdEBEBRATT-Ed Member Posts: 6,930
    @DeniseNickel ,

    Nothing to do with the smell but he did not follow the MFG. piping instructions. Get the boiler manual and show him the piping diagram. Yours is piped wrong unfortunately. Doesn't matter if he has 20, 30 or 40 years experience or has installed 1000 boilers (which is what he will tell you) it's wrong.

    Another installer who flunked reading in school.

    The equalizer is piped wron and the water make-up goes in the boiler above the boiler water line.

    Can't tell if the piping is the correct size from the picture
    delta T1MatthiasDeniseNickelGBart
  • gerry gillgerry gill Member Posts: 2,962
    edited April 2018
    may not be anything but here is a thought also. If there is a floor drain in the basement with a dried up trap seal, when the boiler turns on it can draw its combustion air via the sewer. We get that call several times a year.
    Another thought is the refractory material may be getting direct flame impingement on it instead of just heat. Refractory stinks when flame touches it.

    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

  • SteamheadSteamhead Member Posts: 13,766
    Well, I hope you haven't given them their final payment. There is something wrong with this job that needs to be fixed immediately.
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • the_donutthe_donut Member Posts: 374
    In the case of dried of floor drain, pour vegetable oil down it. It won’t evaporate in the trap like water and won’t mix with incoming water keeping a seal.
  • scottnjrscottnjr Member Posts: 60
    Hi all, check the link that user “the donut” linked to above. That was my saga with a smelly steam boiler Last year. That boiler you have there looks like a weil mclain with a differnt name badge. If so, i happen to know from my ordeal that weil mclain just uses vegetable oil on the units, and its cleaned off before sale. I cant quite tell for sure by the pics if they used blue tape, but if the odor is “chemical” thats what it is. The contractor wont believe it, but in the case i had, removing the tape and using pipe dope fixed the problem. I got no call backs this winter for odor on that job, and the lady was super sensitive.
  • Dave0176Dave0176 Member Posts: 1,101
    The piping don’t look too good either, nor do I see a skim tap installed or even look like it was installed. So there couldn’t be anyway they skimmed the boiler properly leaving cutting oils and what not in the system to smell away.
    DL Mechanical LLC Heating, Cooling and Plumbing 732-266-5386
    NJ Master HVACR Lic# 4630
    Specializing in Steam Heating, Serving the residents of New Jersey

    I cannot force people to spend money, I can only suggest how to spend it wisely.......
  • Jamie HallJamie Hall Member Posts: 12,698
    I think I see blue something on the threads -- can't tell if it's tape or dope, but could be the problem...
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • SuperTechSuperTech Member Posts: 1,303
    > @Jamie Hall said:
    > I think I see blue something on the threads -- can't tell if it's tape or dope, but could be the problem...

    I don't think that's proper pipe dope or Teflon tape. That looks like leak lock to me. Not sure if that would cause the odors like some of the pipe dope does but being unable to skim the boiler must be a huge factor.
  • GBartGBart Member Posts: 753
    edited May 2018
    Also when all issues are addressed the pipes need to be insulated as well.

    A picture IS worth a thousand words.

    Seriously, Steam 101, all pipes have to be insulated or the steam will return to condensate before it gets to the radiators.
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