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B-Vent Leaking When It Rains

Sandrocchia
Sandrocchia Member Posts: 2
in Domestic Hot Water
I’ve been reading some forums about leaking b-vents and can’t seem to find any solutions. Our b-vent is leaking only when it rains. We’ve had a roofer and an HVAC tech come and look but no resolution. The roofer checked the flashing and put silicone around the collar. The HVAC tech put silicone around a seam. After all that, the rain is still coming in, running between the exterior and interior pipes. I’ve included some pictures (albeit from the winter)  
Has anyone ever experienced the same?

Comments

  • HVACNUT
    HVACNUT Member Posts: 6,234
    edited June 2023
    What's that ring below the cap? I've never seen that.

    If you're positive it's coming in between the pipes then the cap has no top, or it's split somewhere. Can't really see the condition of the storm collar.
    Can you see anything from the attic?
    Can you take the cap off and see the condition of the inner pipe, or look up from below?

    I had a roof leak for 2 years. My wife not trusting roofers, ("they'll say we need to replace the whole roof") and assuming I must know how to fix anything, just because I'm in the HVAC trade, therefore I must know how to do everything. My brain says "let's do it." but my body says "you must be smoking crack." It tested our love but we made it through. The "You should watch a YouTube video." comment almost put it over the edge. 
    Numerous times I thought I found it. It would downpour for hours, and dry as a bone. Then we'd get a light windy rain and it would leak.

    So after many attempts I finally found it, then found a roofing company to do the repair only. It took them 2 tries to get it, but that chapter is finally done. And everyone lived to tell about it. 
    Larry Weingarten
  • kcopp
    kcopp Member Posts: 4,462
    I also want to know what that circle is on the top. It does not look like its pitched. It the top the sam mfg as the B-vent? There are a few diff Mfg of b-vent and they are brand specific and parts cant be interchanged...Its a system.
    Make sure your cap and your pipe are the same brand.
  • hot_rod
    hot_rod Member Posts: 23,086
    The top cap should seal the space between the two pipes, inner and outer.

    Looks like an additional storm collar was added to try and seal that vent cap connection.

    Odd not to see guy wires on that tall of a flue pipe. Must of had draft issues to be up so tall?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    GGross
  • JUGHNE
    JUGHNE Member Posts: 11,254
    Silly question; has anyone ever seen "B" vent installed upside down?

    If so that would let rain get between the inner and outer pipes.
    kcopp
  • Larry Weingarten
    Larry Weingarten Member Posts: 3,563
    Hi, Might be time to get up there with a hose when things are otherwise dry, and starting down low, spray different areas and see when water appears inside. That will help you to narrow down where the water is really coming from.

    Yours, Larry
  • Sandrocchia
    Sandrocchia Member Posts: 2
    Thanks for your advice everyone. Not sure what that ring is but I should mention that I’m in Ontario, Canada and all the houses around me have similar variations to this. We are not original owners and this house was built in 1984 so might be something that was standard back then. The pipe looks a bit newer than my neighbours so I’m wondering if it was a replacement when the hot water tank was updated. Will have to investigate more but will also try your suggestion of going up there with a hose and testing it out. Appreciate the help!
  • HomerJSmith
    HomerJSmith Member Posts: 2,593
    Where is it leaking? Caulk around the storm collar to the b vent.

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