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Gas boiler to fit 6" chimney liner ??

lmk Member Posts: 1
We had a contractor in to switch from oil burner (circa 1949) to gas for our steam heated (radiators) house which was built in 1885. The contractor said the first thing we had to do was get the chimney lined. We did that - and the chimney repair guy said the widest flue he could fit into the chimney was a 6" flue. Now the original contractor says there is no gas boiler which will fit a 6" flue! So it appears that we threw $2,000.00 down the drain - or up the chimney! Are we stuck converting to a newer oil burner or can I find a gas burner to work with the new chimney liner?


  • lchmb
    lchmb Member Posts: 2,997

    Size boiler are they trying to install? That's the most important thing to start. Was your chimney guy aware of what you were installing? If so, why did he bother to line it if the boiler was to big for it? I generally like to get involved when I'm doing an install and it needs a liner..that way there are no mistakes..
  • Tim McElwain
    Tim McElwain Member Posts: 4,481
    Need to know some things

    is this boiler natural draft or fan assisted?

    Is there any other equipment going into the liner?

    What is the input to the boiler?

    Who makes the liner and what are their specifications on the amount of BTU it can handle?

    I would get the two contractors together and see if something can be done to resolve this issue.

    By the way if the six inch will not handle gas boiler BTU's what makes anyone think that it will handle an equal BTU oil boiler?
  • Techman
    Techman Member Posts: 2,144

    What size boiler vented into the existing chimney? What size flue pipe went from the boiler to the chimney ? Oil nozzle size? Is the chimney an "innie" or an "outtie" ?
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,195
    Steam boilers come as small as 4" flue pipes.

    The question is what size does your system require? How did the contractor size your replacement boiler?
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
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