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Steam velocity

Does reduction of pipe diameter have an affect on steam velocity ? I have a few radiators that branch off the 2 inch main with 1 inch pipe . thank


  • Jamie HallJamie Hall Member Posts: 9,387
    Of course. For a given amount of steam, the smaller the diameter pipe will have a greater velocity. However, the smaller diameter pipe will also have more friction, so the amount of steam which can be run through a small pipe for a given pressure difference will be reduced.

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • EBEBRATT-EdEBEBRATT-Ed Member Posts: 4,739
    The size of the branch piping to each radiator is based on the the heating capacity of the radiator. It also depends on the type of system you have (1 pipe or 2 pipe).

    Cant cheat on the pipe size (especially on 1 pipe systems) as the condensate flows counterflow to the steam.
  • gerry gillgerry gill Member Posts: 2,876
    you got three radiators on a 1'' pipe??

    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

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