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system pressure is rising........!

My hydronic loop pressure is normally about 14PSI.  I have a Watts feed water pressure regulator/relief valve. The relief valve is set at 30 lbs; it only begins dripping at 35 lbs.  I've never seen the relief valve completely open.  My questions:

Should I replace the relief valve, since it's not completely opening at 30 lbs?

Why is my system pressure running higher than normal?



  • Robert_25
    Robert_25 Member Posts: 530

    Assuming your Watts feed water regular is working properly, I would see if the expansion tank is waterlogged.  Also, if you get domestic hot water from the boiler you could have a pinhole in the tankless coil.
  • Bruce_22
    Bruce_22 Member Posts: 3
    system pressure

    Thanks - I'll drain my expansion tank and see what happens. 
  • Merc
    Merc Member Posts: 4

    If you have an indirect DHW tank and other solutions aren't working, turn the fill system off and watch the pressure hour by hour.  If the pressure doesn't drop (and the gauge works) but water is still leaking out of the relief drain the tank is cross-connected inside.  Turn off domestic water to the tank to confirm.   Certain brands, which I shouldn't name, are prone to this.

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