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new boiler sending odor through the house

SKSK Member Posts: 5
We installed a new Weil McLain steam heat boiler about a month ago. An odor filled the basement right after installation but it was infrequent because of the mild weather. Hot water is also produced by the boiler. We contacted the installer, a major area oil company, who first said it's new boiler smell from coatings that have to burn off, give it a few days. A few days later, still smells. Company made 2 visits. The first tech said the "insulation in the fire box had to cure" but since the boiler wasn't running regularly it might take a few cold days. A few cold days later smell continued and of course got worse since the boiler was running. New tech came out, same answer, needs a few more days for everything to work through the system. Few days more, still stinks throughout the house- a sort of sweet mix of bbq and oil. Supervisor came out and noticed a leak in one of the relief valves. Valves were replaced on Saturday and they drained the boiler and dumped some "silicon" chemical that sent a harsh acrid smell over the house that took most of the day and night to dissipate. So we were told a few cycles and all would be good. Not so. Now Monday and the basement still stinks from the original odor, it's still coming through the house, maybe just a little less. But could be the 2 fans we have going 24 hours to try to move the air out. It's a month now, the basement stinks, I've got no good answers from the company and I'd like to know what I'm smelling, which cannot be great to be breathing with closed windows in the winter. The company says this is the first time they've ever had this issue and make it sound like everyone has smelly boilers and I think they expect us to just get used to it. By the way, we lived here for 25 years with the original boiler without any smell issues. The firebox was worn on the old unit and we were advised we might as well replace the whole thing rather than repair. Now we're worse off than before. Any ideas, solutions, answers?


  • JUGHNEJUGHNE Member Posts: 7,861
    Is this a one pipe steam with a single pipe connection on one end of the radiator and a small air vent on the other.
    Does the smell seem to come from the air vents?

    There would/should be air vents on the main pipes in the basement, which would let air out of the system and maybe smell up the basement.

    They should skim the boiler and get the oils off the top of the water. The new work requires pipe threading oil which will wash back into the water and try to boil off.

    Post pictures of the boiler showing the piping around it, floor to ceiling. We could tell more with that.
  • IronmanIronman Member Posts: 6,139
    Is that a one or two pipe steam system? Do the radiators have individual vents? Is there any odor coming from them?

    You'll get a lot more responses by moving this thread to the steam section.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • SKSK Member Posts: 5
    It is a one pipe system with one pipe into the radiator and air vent on the other side. The smell is not from the radiator vents- definitely from the boiler. They drained the boiler on Saturday but my wife suggested they skim the boiler (she did some internet searches), but techs said that wouldn't help. It's been a month so I would have expected any of the pipe threading oil would not still be affecting things.
  • JUGHNEJUGHNE Member Posts: 7,861
    The fact that when they put the "silicon" into the water the new smell came out of the boiler water for 2 days, makes one think that the original smell is from the boiler water.

    When you drain the water out the bottom, oils will cling to the inside surface and float to the top of the water when refilled.
    Picture of the sight glass?
  • FredFred Member Posts: 8,500
    You know, this problem has surfaced a couple times in the past two years. As a matter of fact, there is a current post on here about a smell from one particular convector. In the prior cases, and it appears even with the current one, though not validated yet, the homeowners finally determined the smell was coming from the teflon tape, used to assemble the piping. When it gets hot, it seems to off-gas. One of the previous Homeowners was a chemist with asthma and she seemed to know her stuff, even though many here didn't believe her.
    Ask your contractor what teflon tape they used on your job and if, by chance they changed brands or ran out while doing your job and bought something they don't typically use. Ask to see the specs for that tape or look it up on the web and see what the tollerance is for temperatures up to 215 degrees. If you can see teflon tape at the joints around the new piping work they did, you may want to try to remove that excess/exposed tape and see if that improves the situation.
    New England SteamWorks
  • SKSK Member Posts: 5
    So sounds like a skim is the correct next step? And my wife noticed the sight glass was not clear- she's been in charge of the boiler and has more hands on than I do on this.
  • I used the old fashioned oil based pipe dope ( Herculues Pro Dope) on my boiler install last year and it still smells a bit when heated. I don't mind it, definitely not harsh/acrid.

    Maybe "silicon" was "silicone" which some varieties release acetic acid (vinegar) on cure and can be extremely irritating in a confined area. This should go away quickly (over a few days). Why they would be using silicone or chemicals inside the boiler is unknown to me (questionable).
  • FredFred Member Posts: 8,500
    @AnthraciteEnergetics said:
    Why they would be using silicone or chemicals inside the boiler is unknown to me (questionable).

    In one post, I think last year, the Homeowner found that the installer had wrapped the teflon tape past the end of the pipes and it was exposed to the steam as it traveled through the pipes.
  • JUGHNEJUGHNE Member Posts: 7,861
    Again Fred, you are right. I even recall that post. It was the one referred to in the Coophammer posting.

    The one from last year, I believe involved unscrewing piping and cleaning the threads. It would be a good time to wash any oil out of the nipples/fittings with Dawn and rinse thoroughly.

    I don't know what they re-piped with for pipe dope.
    But IIRC it did renew the ongoing controversy concerning the boxer/briefs discussion of pipe sealant. Always educational, really.
  • SKSK Member Posts: 5

  • KC_JonesKC_Jones Member Posts: 4,552
    Considering they didn't install the skim tapping, it's going to make it really hard to skim that boiler. Not saying that is your problem, but that is an additional problem.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • FredFred Member Posts: 8,500
    Take that plug out of the boiler and install a nipple and ball valve or Cap, now while the boiler is new. Waiting a year will make adding a skim port a real challenge for you.
  • FredFred Member Posts: 8,500
    I am also wondering if the smell might be from the combination of incompatible pipe dope and tape and if there might be some kind of chemical reaction between the two when heated.
  • SKSK Member Posts: 5
    Here are pics of the glass tube and pail of drained water.
  • FredFred Member Posts: 8,500
    edited November 2017
    It looks like there is oil on top of the water in the sight glass and the boiler needs skimming but that usually doesn't cause an odor throughout the house.
  • Fred said:

    It looks like there is oil on top of the water in the sight glass and the boiler needs skimming but that usually doesn't cause an odor throughout the house.

    Well, it can on a one pipe system via the radiator vents if the smell originates in the boiler water...

    New England SteamWorks
    Service, Installation, & Restoration of Steam Heating Systems
  • LizaLiza Member Posts: 1
    Were you ever able to find out what the issue was? We are having the exact same problem at our new house and no one can figure it out.
  • ethicalpaulethicalpaul Member Posts: 2,523
    Hi @Liza and welcome. If you start a new discussion and describe what you are experiencing and what they have tried so far we can give you some tips.
    1 pipe Peerless 63-03L in Cedar Grove, NJ, coal > oil > NG

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