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multiple gas furnace venting

tomack htg/ac
tomack htg/ac Member Posts: 2
in THE MAIN WALL
Here is the question... I have 6 gas Hot/water boilers to install (all with 4" vent) what size vent in the Chimney do I need ? That is one house, the other has 4 of the same going in. In both these multi-families there is one Oil hot/water boiler at present, that will be used for indirect D/H/W

Comments

  • [Deleted User]
    [Deleted User] Posts: 29
    Get hold of NFPA 54

    and use the proper venting tables. This will insure that you meet the "MIN" and "MAX" requirements for vents.

    It sounds like you are going to use the existing chimney for a chase and use a chimney liner. Be advised most chimney liners have a 20% reduction requirement for capacity from the tables.

    Another suggestion is to use double wall pipe which will give you more capacity when used all the way from the draft hood.

    Are these boilers power vented or fan assited? If so that changes things also.

    Another concern for you to address is "Air for Combustion". Do you have adequate air for combustion in the boiler area?
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