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Boiler not holding water pressure

EddieHEddieH Member Posts: 5
So I have a water heater and boiler that seems to work fine, the pilot light is lit but no heat is coming through vents. The boiler temperature itself is showing about 70 degrees but water pressure psi is at 0 and will not move even when I add water to it. I have attached some pics any help would be appreciated.


  • HVACNUTHVACNUT Member Posts: 1,729
    Actually the boiler temp is 165° F according to the gauge.
    Stand back and take some pics of the whole system. Boiler, water heater, piping.
    Seems like the boiler is not moving water. Possibly a circulator or relay. More info is needed.
  • GilmorrieGilmorrie Member Posts: 93
    According to the photos of the gauge, the pressure is zero. Jack it up to about 15-20 psi.
  • Jamie HallJamie Hall Member Posts: 9,383
    You say that the pressure will not move even when you add water to the system? There are only two possibilities there -- either the gauge is broken (it happens) or you have a bad leak somewhere. Best to find out and fix...

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • EddieHEddieH Member Posts: 5
  • EddieHEddieH Member Posts: 5
    Bled my heaters yesterday felt a little heat come out but still no water pressure I have stop trying to feed water
  • JUGHNEJUGHNE Member Posts: 5,124
    If you get no air or water out of the heaters, then your auto feeder is stuck shut.

    Do not run the boiler without water.

    Do not add water to the boiler when it is too hot to hold your hand on the bottom heating pipe.

    You may need to call a pro.
  • GordyGordy Member Posts: 8,654
    edited January 12
    Im thinking from your description the gauge is not functioning. If you are bleeding radiators, and getting fluid, or air there must be pressure in the system. What elevation is the highest emitter? Two story home?

    Buy a psi gauge, and adapters to hook up to the boiler drain to verify gauge psi reading.

    Another possibility is the feeder valve is plugged, or inoperative . Remove strainer screen, and clean.
  • EddieHEddieH Member Posts: 5
    When I bled the heaters got a little bit of water and definitely, some air came out for about 5 mins
  • GordyGordy Member Posts: 8,654
    edited January 12
    Was someone adding water while you were bleeding for that five minutes? That's a long time to bleed without makeup water being added. The pressure reducing valve will not keep up unless you are using the fast fill lever.
  • EddieHEddieH Member Posts: 5
    Yes I add water afterwards, but the gauge still has not moved starting to think it is something wrong with my gauge
  • GordyGordy Member Posts: 8,654
    Verify gauge as I noted.
  • Intplm.Intplm. Member Posts: 72
    Can you remove the gauge ? Clean the port on the boiler and the small port on the gauge? Tap the thing?
    Try not to do more damage and have a replacement with you. The best thing to do at this point may be just to change it.
  • GordyGordy Member Posts: 8,654
    Changing the gauge is a little more involved if isolation valves at the boiler are not in place. I recommended a control psi gauge to be sure it is indeed the gauge that is corrupt. After verifying, then pursuing the installation of a new tridictator is a the next step. However until the heating season fades the alternate psi gauge will get the poster by.
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