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Degree of boiler floor level?

Hi folks -

I'm in the middle of a new WM steam boiler installation. Contractor is a respected outfit for steam heat, skilled crew, but they mentioned something about the pad level looking a little off. They'll be back tomorrow to finish the installation including the near piping but going down to check it out in detail this evening there's a 5/8" tilt towards the water feeder side. Is there a rule of thumb on how level this needs to be?

For all I know, they plan to remedy it in the morning, but I'd really like to have an idea of whether this tilt is within reason or if I need to fall on my sword for this since this is a (hopefully) one-in-several-decade process. And, if it's too much tilt, I'd sure like to nip it in the bud before the installation is finished. Similarly, what's the consensus on [metal] shimming it?


  • Steamhead
    Steamhead Member Posts: 15,025
    The boiler should be level. Shim it as needed.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    New England SteamWorksdelta TJim_R
  • BobC
    BobC Member Posts: 5,255
    Use aluminum shims so rust won't be an issue.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • I use plastic shims from Amazon, but shims will do. When you install steam boilers, -a level surface is a real luxury.

    Dirt with rocks is kind of normal....
    New England SteamWorks
    Service, Installation, & Restoration of Steam Heating Systems
    EBEBRATT-Ed Member Posts: 11,101
    4" square electrical box covers make good shims cheap and readily available at the hardware store
    Canuckerdelta T