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HB Smith -- boiler gap

Hello everyone. I need help for finding which material should I use for cover the gap in front of the boiler? The NY State inspector said we should cover the gap asap.

Please help for this. Thank you.



  • retiredguy
    retiredguy Member Posts: 922
    There should be a blue piece of metal, the same color as the jacket, that fills in that gap between the doors. That metal piece is only for show and does not serve any function. When the burner fires, no amount of flue gases or air should move in or out of that gap. Most of the time, that piece was thrown away by the servicing company since it served no purpose. That inspector is probably new or does not have any history with H B Smith 450 boilers. I would ask him "nicely" why he wants that gap covered. If products of combustion or air is felt moving through that gap then there is a real problems like the rope gasket on the flue door missing or deteriorated. By the way, Is that an old North American burner mounted on that boiler?
  • ScottSecor
    ScottSecor Member Posts: 863
    I agree with @retiredguy with regard to the missing metal plate. However, in your second photo I notice what appears to be some sort of door sealing that has fallen down. It is critical that both front doors are properly sealed so no fumes can escape into the room. We have used non-asbestos rope and Kaowool tape with success to seal the doors on the 450 and 350 Mills boilers.

    EBEBRATT-Ed Member Posts: 15,767

    If you loosened all the bolts on the doors they swing open. There is rope (probably asbestos) which can be replaced with fiber rope. It installed in groove on the inside of the doors and glued in place.

    If the doors are sealing ok, just by some "kaowool blanket" at a heating supply house and stuff it in the crack to keep it sealed. It does nothing as long as the door sealing inside the door is intact., but may satisfy the inspector.


    That's a burner I grew up on.

    That is an Iron Fireman air atomizing burner (I can see the air compressor air intake filter in the corner of the picture) so it's either a AO-6.3 (45 gph) or an AO-9.8 (70 gph) they were sold for 2, 4, or 6 oil with or without gas using the same frame burner.

    I can see enough to tell it.s not #6 oil

    It could be #2 or #4 oil the only difference would be the electric oil heater which isn't in the picture

    Since the boiler is a 450 it's probably an AO-4-6.3 45 gallon/hr #4 oil
  • SteamingatMohawk
    SteamingatMohawk Member Posts: 1,024
    Is that the boiler from "Home Alone"? Scary looking.
  • videoshim
    videoshim Member Posts: 3
    Thank you so much for reply from all of you.