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relief valve leak

paul41 Member Posts: 1
relief valve leaking on an Laars EBP system. How to diagnose


  • Jamie Hall
    Jamie Hall Member Posts: 23,447
    Relief valve? The system pressure relief valve? Is there a pressure gauge on the system (there should be)? What does it read with the heat off? With the heat on?

    A note: the system pressure relief valve is a safety device. If it is leaking, you will need to replace it -- but you must find out why it opened in the first place, and for that you need the pressure readings. For starters. Then we can go farther...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • rudyshlesinger
    rudyshlesinger Member Posts: 15
    check the expansion tank, right size ?, malfunctioned ?
  • Zman
    Zman Member Posts: 7,573
    A picture would help. If is an EPB combi there will 2 valves.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • hot_rod
    hot_rod Member Posts: 22,263
    Be sure the gauge is reading accurately, considering adding a quick and easy hose thread type test gauge somewhere on the boiler, to double check the pressure.

    Fill valve and or expansion tank are two places to look for pressure increase instigators.

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • GroundUp
    GroundUp Member Posts: 1,926
    Has pressure risen to the point of needing relief? Has someone used the relief valve to bleed air or pressure? Either of those can get a chunk of crap in the seat and cause them to dribble.

    Has the system been in operation awhile or is it new? What brand is the valve? I bought a case of Watts 30# valves last fall and every single one of them dribbled through at 10 PSI. After 4 in a row leaked on the same job same day, I screwed in an Apollo and went home. Took every single one out of the boxes and tested to 10 psi hydro and they all did the same thing. Expensive case of scrap brass is all that was