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Boiler Replacement

Hi guys, I'm licensed for both plumbing and heating. I have to replace a steam boiler and I'm definitely not the guy who fully knows steam. I've done my share, but this one I'm asking around.
Here's the deal it's a system that has been capped off multiple times. There is a 4"main that used to do an entire building. As of now, it's only serving 6 radiators. 2 in interior bathrooms, 1 in a foyer, 3 in a room which is also heated with an AH. So... I'd love to downsize the boiler, but not sure with the 4"main if I'll run into surging or other problems. Any thoughts would be appreciated. Thanks!


  • Jamie Hall
    Jamie Hall Member Posts: 23,317
    The 4 inch man won't give you any trouble -- provided yo I insulate it thoroughly and make sure it's properly sloped and dripped. Not a problem.

    Do size the replacement boiler to the connected EDR, though!
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England