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Steam Oil Fired Boiler filling up with water

84maple
84maple Member Posts: 5


Hello,

Looking for some suggestions please. Weil Mclain (1998) with McDonnell No 101-A water valve. Works fine in summer, once cold temps hit and heat is on the water gauge (site glass) starts filling up to the point where the boiler will not work and buckets of water have to be emptied to get it working. This has happened 5-8 times over last couple of years. I have had two professionals inspect and this has been the only resolution so far. This usually works. However yesterday it turned off, I emptied bucket of water, it came back on but the radiators were all making crazy banging noises which is not normal and then it shut down - I thought because it had reached temp but today it did not come on again. I emptied about 10-15 gallons, got the water level down to center of sight glass and turned the boiler on and it fired up immediately. Problem is as soon as I turned the boiler back on the red button on the water valve depresses and starts putting back all the water I emptied so I just shut it off. Any suggestions. Can that valve be shut off?

Comments

  • Jamie Hall
    Jamie Hall Member Posts: 24,713
    There should be a manual shutoff valve -- or preferably even two, to isolate -- on the line for the autofeeder. Just close them -- but remember that then the autofeeder won't work.

    Problem. Now you have to keep an eye on the water level.

    Second problem. The actual problem may not be in the autofeeder, but in your low water cutoff. That often controls the autofeeder, and it may be busted. It would be a very good idea to make sure that it does, indeed, shut off the boiler if the water gets too low.

    It would be a better idea if you got someone out there who knows steam systems to go over this and check it... and fix it...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,381
    Post some pictures of the boiler and the piping above and around it so we can see what is going on.

    For now isolate the feeder as @Jamie Hall said and see how things run. The low water cutoff could well be the problem. Could have a float inside that is damaged.
  • Jamie Hall
    Jamie Hall Member Posts: 24,713
    to add to my previous post -- the observation that the red button pulls down when power is applied suggests to me very strongly that the problem may not be the feeder, but the low water cutoff. That type of cutoff needs to be blown down once in a while -- weekly to monthly -- as it has a float in it when can get obstructed by crud.

    That said, it may be that the float is hung up on a low level. Whoch would activate the feeder. But... which should also prevent the boiler from firing. Which further suggests that you need to have that low water cutoff carefully examined and, if necessary, repaired or replaced... dangerous to run a boiler without a functioning LWCO.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Erin Holohan Haskell
    Erin Holohan Haskell Member, Moderator, Administrator Posts: 2,354
    @84maple, I've merged your duplicate posts into one here.

    President
    HeatingHelp.com

  • 84maple
    84maple Member Posts: 5
    Thank you Erin
    Erin Holohan Haskell
  • Steamhead
    Steamhead Member Posts: 17,359
    @84maple , where are you located? Looks like you need a pro, and we might know someone.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
  • 84maple
    84maple Member Posts: 5
    Jamie, I had someone out to take a look and it turns out I do not have a manual shut off valve... and you were right the float was hung up on low level. Tapped each side with a hammer and that was enough to release it. Not too hard to damage the casing, just hard enough to release it. Did some flushing and tests and it working fine. Thank you for your recommendations!
    HVACNUT
  • Big Ed_4
    Big Ed_4 Member Posts: 3,004
    edited November 2023
    The mud in the gauge ... The new Home Depot bucket at the blow down . I would lean into the 67 float assembly ....

    There was an error rendering this rich post.

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,381
    @84maple

    Just a little advice to take somewhat seriously. I don't want to see you have to buy a new boiler when you don't need one yet.

    If the float in the #67 low water cut off was hanging up and messing with the water feeder then it could just as easily hang up and not shut the burner down on low water.

    You should take the low water cutoff apart and clean it or replace the entire control. MM recommends replacement after 10 years or so but that is your call. New ones do cost $$$ but far less than a new boiler.
    HVACNUT
  • neilc
    neilc Member Posts: 2,841
    Big Ed_4 said:

    The mud in the gauge ... The new Home Depot bucket at the blow down . I would lean into the 67 float assembly ....

    84,
    what Big Ed wrote, "lean into the 67",
    you ought be blowing down that LWCO on a regular, weekly, basis,
    do this while the boiler burner is firing,
    open the blowdown valve wide open, until water drops in the sightglass, and turns off the burner,
    and also until the water runs clean, expect the start of the blowdown to be murky muddy, gasps of steam are to be expected, and I don't mean crystal clear, just clearer than the beginning mud and murk.
    If the burner does not shut down when blowing down, shut off the boiler and get the LWCO fixed.
    known to beat dead horses
    HVACNUT
  • BobC
    BobC Member Posts: 5,501
    For thae last 30 years I've had probe type low water cufoffs and never had a problem with them. I just sest them a few times a year to make sure does shut the boiler down if the water does get to low. Probe type LWCO's are not cheap but they are a lot cheaper than float types.

    I keep by boiler water at a high PH to control corrosion so I only clean and remove that probe every few years and it's been clean every time so far.

    Bob
    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
    CLamb