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Honeywell pressuretrol

DJR Member Posts: 1
I'm trying to determine the best initial setting for the Honeywell pressuretrol in the attached photo. Just bought an older home with an AGP Boiler and have been reading "we got steam heat". But I cannot tell whether this is a subtractive diff control or not. Does anyone know how I should set this particular control initially - and adjust it as I work to get steam to all radiators? I understand the concept Dan talks about in his book about the cut in of .5 psi and the cut out of 1.5 psi. Just now sure how to set that on this control.

Thanks for any ideas or help.


  • Enreynolds
    Enreynolds Member Posts: 119
    Additive diferential

    DJR, on your control, the left hand scale is the cut in point which should be set at .5 psi, if it is possible.  The right hand scale is the differential, which you should set at 1.0 psi.  The cut out  is the cut in plus the differential.  That being said, could you post some pictures of your boiler, the piping around it, and any odd looking equipment/cast-iron pieces that may be hanging around the boiler room.   Take pictures from back away so we can see how and where pipes are connected.  We can always zoom in for detail, and we may be able to help you better this way.

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