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Outdoor boiler leak

Tom_133 Member Posts: 888
Hey all,

Got a buddy who just found his outdoor boiler leaking in several spots, not pouring out, just small leaks. He has come to terms with a new boiler, but things are tight and he would like to see if he can limp it along this winter. Anyone had success putting boiler stop leak in with a situation like this?

Its a no PSI, atmospheric wood boiler. Sorry I dont know the brand.

Any thoughts? Suggestions?

Montpelier Vt


  • hot_rod
    hot_rod Member Posts: 22,254
    Fernox F4 might work
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    Fire side, or outside leak? Can it be welded? I've welded a boiler on the fireside, not bad if you can get to it and not be all curled up in a ball inside! A stick welder and a grinder are your friend. Be sure to wear proper lung protection.
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • EYoder
    EYoder Member Posts: 60
    If it's a very small seepage we've used some Hercules stop leak and it worked. Bigger leak probably won't.
    It's pretty early in the season to trust stop leak all winter tho... 😬