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Leaky boiler

I have a 10 year old Buderus triple-pass, three section, cold start boiler.  It either has a leak in the gasket between sections or a fissure in one of the section castings.  It does not drip, but has probably been defective since new.  I only recently became aware of the problem because the outer blue metal jacket corroded through.  The insulation jacket is all black with mold from the misting of the leak making exact location difficult, but I have it down to a 4 inch circle.  Buderus will provide a new boiler block but I must bear the $2400 charge for installation.  Is there a stop-leak product that I can introduce into the boiler or a boiler cement that can be used on the outside to repair this?  Lacking either of these solutions, is there a reliable home boiler repair outfit that I can use?  I live in Snyder Co. central PA. 


  • Further info

    I have removed the side covers and done a little extra "poking around" and have discovered that the leak is in the seam between two boiler sections.  It's approximately three eighth of an inch long.  It looks as though there was a gap in the original gasket sealing compound which was used to seal the sections.  There is excess of squeezed-out compound all around the seam except where it's leaking.  I could actually see the steam vapor shooting out at that spot when the boiler fired up.  Could this gap be brazed shut or is their a boiler cement that would hold?  The boiler only runs at 15 - 17 lbs pressure. 
  • meplumber
    meplumber Member Posts: 678
    Have your contractor contact Buderus.

    The best solution would be for you to have the original installing contractor contact Buderus. They will send a rep out to take a look. They are not as negotiable with homeowners as they are with their contractors.

    The problem that you described is a problem from assembly at the factory, since the G115/21's were not shipped in knock down form.

    Contact the installer and have him make the call.

    Good Luck.
  • lchmb
    lchmb Member Posts: 2,997

    There is no way to cement the section and although stop leak may slow it down, it's only a patch to the problem. Your better off to get the replacement block and have it installed to solve your problem completely.. Unfortunately they will only replace the block, not the labor to do it...
  • meplumber
    meplumber Member Posts: 678
    FYI for Ichmb

    I had a case similar a few years back. Since it was a manufacturing issue and not an installation issue, Buderus did help out on the labor at a prorated amount.

    Since this has been in 10 years, they may not in this case, but it is worth a try.

    Just wanted to let you know in case you ever run across one.
  • lchmb
    lchmb Member Posts: 2,997

    It never hurts to ask and anything will help without a doubt. They are an excellent company so you never know...I'll keep that in the back of my mind..:)
  • icesailor
    icesailor Member Posts: 7,265
    Stop Leak:

    My old High School Auto Shop teacher always said, "You can't buy a mechanic in a can.

    50 years later, I have found that to be 100% true. I tried a few times but it always failed in the end. There are no short-cuts when it comes to heating system leaks.
  • billtwocase
    billtwocase Member Posts: 2,385
    in a case like this

    warranty replacement is always the way to go, but I will add that I have pumped Permaweld into leaking boilers, and they have performed leakless for years. A good sealer will do the job. Cartridge circs don't like it too much though
  • Thanks

    Thank you all for your input.  Since the original installer has gone out of business I have contacted my boiler maintenance group and they are getting a replacement block from Buderus for me.  Thanks again for the input. 
This discussion has been closed.