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steam rad vent - adjustable

Rick T
Rick T Member Posts: 15
On a Hoffman 1A adjustable vent, is the fastest setting equal to a non adjustable vent (Hoffman 40), or is it the middle number?


  • gfrbrookline
    gfrbrookline Member Posts: 686
    A Hoffman 1A vents between .020 and .145, a Hoffman 40 vents at .042. I prefer Ventrite No.1's as the are easier to adjust. It can be difficult to get the screw cap to seat properly in the Hoffman 1A, the knob on the Ventrite just turns so is fool proof.
  • Fred
    Fred Member Posts: 8,518
    At setting #4, the Hoffman 1A vents at about the same rate as a #40.