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Slightly low water level

CoreyT Member Posts: 13

I started up the heating system today to make sure all is well for the winter and after about 20 minutes I thought all was well. I checked the boiler afterwards and found the water level was very low, about 2" from the bottom maybe, and the low water cut off light was on. I tried using my water feeder to bring the level back up, but it just doesn't seem to move. I've never done this before so I'm not sure if I'm doing anything wrong, so hopefully you guys can help me. The level has come back up a bit since the system has been off for a couple hours, from what I have learned here I believe that would be from the condensate getting back into the system. Below is are two pics of the system hopefully they help. I looked in the manuals, but everything I have is about installation and startup though.


  • crash2009
    crash2009 Member Posts: 1,484
    edited October 2012
    I'll get the picture

     right side up for you.
  • CoreyT
    CoreyT Member Posts: 13

    haha, oops. I didn't notice that until just now. Weird since the photo was taken right side up.
  • crash2009
    crash2009 Member Posts: 1,484
    Did you happen to notice

     what the pressure gauge was reading during your first start?
  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,815
    Hartford Loop

    I can't see where the Hartford loop is in the pictures, but if it's 2" below NWL, there might be a leak in the wet return.
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
  • CoreyT
    CoreyT Member Posts: 13
    Water level

    The level before I turned it on was about 1/4" above the water line.

    I think the Hartford loop is fine on the system. I didn't have any noticeable issues last year, and it was serviced. I also posted pics of the system up here when I moved in last year and people said it looked ok.
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,573
    Low water in the boiler

    There could be a leak in the return line which is leaking unseen into the ground, unseen.

    The other cause could be over-pressure forcing the water out of the boiler into the returns, while it it firing somewhat uncontrollably. This can temporarily starve the boiler of water, and then it always comes back. During this situation, water could be added during this excessive steaming, and would be immediately forced up into the returns.

    I would turn off the valve to the water feeder, and leave it closed. I would also get a good low-pressure gauge, (0-3 psi) so you know what the pressure is in the system. Lower pressure is better, such as 2 ounces, which can only be achieved with a vaporstat, and massive main venting.--NBC
  • fixitguy
    fixitguy Member Posts: 91
    Maybe not

    It could be a false level. I often see a plugged port at the bottom of the sight glass and may need to be reamed out with a coat hanger.
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