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vintage boiler firebox repair?

so here's my take. firebrick can be used,also a universal blanket-type system can be installed if you can access the inside of the boiler. Older Lennox F/A furnaces had special curved firebrick which is VERY durable,but no longer available (???) It's a dirty job,but not impossible.


  • Jay_21
    Jay_21 Member Posts: 6
    Vintage boiler firebox repair frustration

    got an esoteric question for the list I hope someone can help with.

    I have a small 1920s oil, round, cast-iron boiler with a recent beckett flame retension burner. It works very well EXCEPT the firebox is badly decayed (deep reddish deposits, crumbling, "mushrooms" of crud, etc).

    The problem I am having is finding someone to replace the firebox. My supplier just changed hands due to retirement and the new techs are reluctant retrained gas techs and young to boot.

    I seriously considered a new gas boiler because of the firebox but am now deeply spooked about rising gas prices. While oil service is a problem, there are still several companies delivering oil and competing. The problem is they all use the same consolidated (outsourced) oil boiler service comany.

    Anyways-The oldtimer tech who serviced the boiler last year said the box replacement was needed, and "no big deal" and quoted about 500$, then he up and retired :-)

    But young techs say its asbestos/they dont make them/
    its original to the boiler and cant be replaced, etc. but really I think they just dont have any idea. In fact, the guy who did the nozzle/filter change said he didnt know how to fix a firebox--he really just seemed to understand the burner unit itself.

    I've called around to other oil suppliers, but essentially oil is highly endangered around here (minnesota) and all the local oil techs have retired, leaving one consolidated company of inexperienced retrained gas men. Although I like oil, I think it would be very risky in my area to invest in a new oil boiler, so that leaves fixing the firebox.


    1) Were fireboxes generally asbestos material? I thought they were rather a ceramic type material. Obviously abatement would be an issue if it is asbestos.

    2) Is replacement that big a deal? I didnt think the firebox was a "part" so much as a box consturcted by the tech on the spot.

    I just dont see how last years oldtimer could say "no big deal" and now its become "impossible".

    I realize without seeing it these are just general questions--but Id sure appreciate any wisdom from the list so I know how to ask for the service we need. Thank you for any advice yo can offer!

  • Sam G._2
    Sam G._2 Member Posts: 17

    I wish I had know this 3 months ago. I just threw out several old (but new) pieced round chambers. There are "wet pack" chambers available to mold to the current shape. (To the best of my knowledge, the original chambers were firebrick, not asbestos)

    If your boiler is that old, make a choice and change it. The savings from increasing effiency will more than make up any price differential.
  • Firedragon_4
    Firedragon_4 Member Posts: 1,436
    Old and new

    combustion chamber 'brick' materials are made from certain clays and limestone. New soft chamber materials beginning in the 1980's were made from fiberglass and other glass based materials.

    From Day One until the 1980's most brick chambers and many soft chambers had asbestos used in the construction of the final chamber in the caps, faces and construction, FACT!

    Get an asbestos abatement company to remove the old one for both you and your family's safety.

    A little more info here: http://www.bnzmaterials.com/zelienople.html
  • \"1920s oil, round, cast-iron boiler\"

    Jay, this thing probably runs at about 45% efficiency even with the Beckett burner on it. You might cut your oil consumption in half by replacing it with a new oil-fired boiler.

    However, if for whatever reason you can't replace it this year, a new firebox can be easily installed. The current ones made from Kaowool reach operating temp much faster than the old brick ones, and are therefore a bit more efficient.

    Tell us more about your system. Is it steam or hot-water?
This discussion has been closed.