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Pressuretrol set screw reassemble?

becca
becca Member Posts: 2
On my Honeywell PA404A, I stupidly took the top cut-in set screw all the way out, while removing the control to clean the pigtail. So the screw was disconnected from the spring inside, but I was able to reinsert it and set the cut-in again at .5psi. My concern is that removing it like this may have changed the calibration. Or should it be ok? I suppose I will run the system and see how it cycles (though I have a useless 30-psi gauge). Wish I could shop-test it! It had been working fine previously. Thanks for any opinions!

Comments

  • 109A_5
    109A_5 Member Posts: 483
    Hello @becca,

    If the adjustment screw, setting indicator and spring is back where it should be and the cylindrical spacer just above the diaphragm and just below the calibration set screw is in its correct location (basically centered under the calibration set screw) it is probably as good as it ever was.

    Testing example;
    Testing the Accuracy of Honeywell Pressuretrol
    https://youtu.be/mE1-QuUx4_c
    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • ethicalpaul
    ethicalpaul Member Posts: 4,192
    Yeah if the indicator is moving up and down you should be fine. I ran mine for awhile with the spring disconnected and that was the only time it actually cut out at 1.5 psi 
    1 pipe Peerless 63-03L in Cedar Grove, NJ, coal > oil > NG
  • jhewings
    jhewings Member Posts: 135
    The results of that test were similar to 2 pressuretrols I have looked at recently.
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 4,967
    That is why it is recommended to use the more expensive Vaporstat L408 series if you need accurate control.
    Edward Young Retired HVAC Contractor & HYDRONICIAN Services first oil burner at age 16 P/T trainer for EH-CC.org
  • becca
    becca Member Posts: 2
    Thanks for the feedback! I’m reassured that I have it back together again, and it’s interesting that it’s  probably not all that exact anyway. Seems to be cycling normally.  Maybe I’ll try testing it with an old BP gauge sometime, ha. 
  • ChrisJ
    ChrisJ Member Posts: 13,887
    becca said:

    Thanks for the feedback! I’m reassured that I have it back together again, and it’s interesting that it’s  probably not all that exact anyway. Seems to be cycling normally.  Maybe I’ll try testing it with an old BP gauge sometime, ha. 

    How much is it cycling, and when?
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • jhewings
    jhewings Member Posts: 135
    A lot of us have a low pressure gauge next to the standard 0-30 gauge. This 0-3 or 0-5 gauge can tell you what your pressure really is. Then if you observe your pressure gets above say 1.5 or 2 psi, you can look at the system and try to improve it, or at least limit the pressure which might require a vaporstat.