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Mystery odor, baseboard loop

GW Member Posts: 4,691
edited February 29 in THE MAIN WALL
I have a customer, we did a steam boiler change-out 8 years ago, and reconnected her small BB zone for an addition that was done in the 80s.

She is adamant that the BB zone is emanating a foul odor, when the zone comes on. She is certain it's coming from the water inside the piping. I told her odor can't permeate copper tubing. She's not blaming us at all. She spoke to the rodent person and is convinced it's not a dead animal.

Two months ago, we had a language barrier (English is her second language) and we went and ran a system cleaner through the steam system. I think it was 8 way. She says the odor issue got better for 2 weeks.

Any wild thoughts?

Gary Wilson
Wilson Services, Inc
Northampton, MA


  • leonz
    leonz Member Posts: 1,122
    edited February 28
    Speaking as a homeowner with hot water baseboard heat; The fin tubes need to be vacuumed and the covers removed to check for debris as old dust can really stink-I hate my baseboard heat.

    There may be a dead mouse in the piping through holes.
    Baking soda always helps too.
  • hot_rod
    hot_rod Member Posts: 22,107
    Any cats in the house?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Jamie Hall
    Jamie Hall Member Posts: 23,273
    Older house, Gary? I'm kind of thinking dead critter on or near a pipe under the floor going to that baseboard... get's nice and warm when the heat comes on.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Larry Weingarten
    Larry Weingarten Member Posts: 3,286
    Hi, Are there any vents on the baseboard in the living space? Can she describe more fully just what the odor is like? Can you take a sample of the water and have her smell it? Perhaps she has a particularly sensitive nose.
    If it's not the water, what's at the baseboard, or what's happening in the space under the bb? Maybe a skunk is living in the crawlspace? Air sealing could help if infiltration is a real problem.
    Now for the wild thoughts: Aliens, Bigfoot, Pigpen, and/or Capybara. :o

    Yours, Larry
  • mattmia2
    mattmia2 Member Posts: 9,623
    edited February 28
    vacuum and spray with an enzymatic cleaner? Refer them to someone who does that sort of cleaning as a business? Make sure there are no bleeders or valve that are leaking and get rid of any automatic vents(although it shouldn't have those on a hot water loop off of steam anyhow)

    Maybe the boiler produces and odor at the boiler when it fires at lower heat for the baseboard? Maybe the ciruclator?

    The same water is getting the air on top of it vented at the steam radiators so it should be much worse there if it was the water.
  • Intplm.
    Intplm. Member Posts: 1,941
    Is there a house pet that frequents that specific area?
    Look for the pet doing something there possibly?
  • ScottSecor
    ScottSecor Member Posts: 855
    My guess is dead mouse, or dead bugs (ladybugs or flies for example). Second guess is an animal used the hwbb as a bathroom in the past. Would not be the first time.
  • GW
    GW Member Posts: 4,691
    Thanks all, I don't know of any animals/pets. I'll send this link to her so she can see some of your comments. My thinking was a dead critter too, but that has been dismissed. Thank you very much
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA