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pressure setting

Empire_2
Empire_2 Member Posts: 2,343
I wish I had the numbers off the control so I could cross match it. Everything is a guess since I dont know what is adj. or if 1 setting is fixed.... I'm not sure.

Mike T.

Comments

  • Irv
    Irv Member Posts: 95
    pressuretrol

    I have a Honeywell pressuretrol looks like a 404a.
    It has settings for differential and cut out.
    On the side of the unit it says "cut in equals cut out plus differential.
    How would I set this for 2lb of pressure??
    Thanks.
  • Empire_2
    Empire_2 Member Posts: 2,343
    Settings

    Are you sure the lable doesen't state, Cut out = cut in plus diff? Look on the inside of the cover for mod #.

    Mike T.
  • Irv
    Irv Member Posts: 95


    I see two numbers on the outside .
    One says C355,
    the other says P404A.
    The outside of the controller says cut in setting equals cut out + diff.
    Thanks.
  • Empire_2
    Empire_2 Member Posts: 2,343
    Try this

    .5 for cut out and (Plus) -2.5 for Diff. The diff in this case seems to be a neg- number. In other words, Cut out is .5 plus -2.5 on the adjustable diff, which will give you .5 cut in. Also the #'s you gave still do not cross match.. You have to look INSIDE the cover.

    Mike T.
  • eddie_6
    eddie_6 Member Posts: 3


    Wouldn't that be the equivalent of 3lbs?
    If I set the cut out at .5 and the differential at lets say
    1.5, then wouldnt the total system pressure be 2?
    That is assuming that as this box says CUT IN equals
    CUT OUT + DiFFential?

    I think perhaps what they are referring to as a cut-in is the point/number at which the pressuretrol would shut off the boiler? I guess I can test it by raising the temp of the thermostat so the boiler builds up pressure?
  • rob brown
    rob brown Member Posts: 69
    cut in

    eddie, set the cut out at 2# thats when the burner stops. then your diff. at .5# then when the pressure drops to .5#, the burner restarts. hope this helps. rob
  • eddie_6
    eddie_6 Member Posts: 3
    cut in

    > eddie, set the cut out at 2# thats when the

    > burner stops. then your diff. at .5# then when

    > the pressure drops to .5#, the burner restarts.

    > hope this helps. rob



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