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differential wheel

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Dwayne B
Dwayne B Posts: 2
in THE MAIN WALL
In Dan's book on The Lost Art of Steam Heating he says to set cut in on a steam boiler to 1/2 psi and set the differential wheel to 1 psi. What is this diff wheel and where do I find it on my boiler. Is it the pressure gage?

Dwayne

Comments

  • Jamie Hall
    Jamie Hall Posts: 27,884
    It's one of the controls

    on the pressuretrol or vapourstat. Some of them are subtractive, some additive. You'll have to look and see which it is.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • scrook_2
    scrook_2 Posts: 610
    Honeywell P-trol

    If it's a common Honeywell PA404A pressuretrol then there's a wheel under its cover for differential (cut-in) adjustment and a screw adjust on top for cutout pressure. See the last page "settings" of:

    http://customer.honeywell.com/techlit/pdf/PackedLit/60-2341.pdf

    Shut off power to your boiler before removing the cover!
  • [Deleted User]
    [Deleted User] Posts: 672
    in dan's 'we got steam heat',

    he details it on pgs 123-126
    Rem77
  • Dwayne B
    Dwayne B Posts: 2


    Thanks to those who responded. It was under the hood of the pressuretrol and I have set it.

    Dwayne B
This discussion has been closed.

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