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confused or short cycle.

nicksxvs
nicksxvs Member Posts: 50
edited November 2020 in Strictly Steam
residential one zone steam boiler. the room temp. is 68, i turned it up to 75 nothing turns on.the water level is high so i start draining the boiler thru the aquastat? after a couple seconds the burner comes on the water is still at the top of the site glass. the pressure guage says 2 pounds. and the limit is set at 1/2 pound.the burner will run for a couple minutes and then it starts filling with water. the burner kicks off. the radiators are lukewarm, half the radiators are turned off to save energy .. it's just had it's yearly clean and check

Comments

  • JUGHNE
    JUGHNE Member Posts: 11,042
    edited November 2020
    The high water level was enough to make the control think there was 2PSI of steam inside....but it was water.

    Shut off the water supply valve and drain the water down to the normal level...about center of sight glass.

    If it fires like it should but then shuts down and the auto fill snaps on you have a problem with probably a probe.

    Your last service should have checked the water fill system, including the probe.

    Is this a one pipe system? If so the valves at the rads you have off may not seal tight. Will then pass some steam and retain it in the radiator as water. Opening them with the system off you might heat water draining back. Possibly overfilling your boiler.

    How about pictures of the boiler and controls, also picture of your typical radiator showing both ends of it.

    What aquastat do you drain the boiler with?
  • neilc
    neilc Member Posts: 2,689
    sounds like the yearly clean missed something, you need a new yearly cleaner.
    post pictures of the pressure gage, the Ptrol, the pigtail, and the sightglass,
    your pigtail is clogged,
    known to beat dead horses
  • nicksxvs
    nicksxvs Member Posts: 50
    i cant get pictures now. they have the same company coming out tomorrow.i'm guessing the weight of the water is causing the 2lb reading.. i think the guage and limit are above the same pigtail.i drained the water out of the black thing with the water level float inside. the boiler was hot so i was afarid to completly drain. and didn't understand why it was coming on. it's out of my hands but i thank you for ur advise.
  • JUGHNE
    JUGHNE Member Posts: 11,042
    Is this the boiler in the church with the feeder pump?
  • nicksxvs
    nicksxvs Member Posts: 50
    no, single home. i should of drained it start from scratch.
  • Jamie Hall
    Jamie Hall Member Posts: 23,160
    If the pressuretrol is set to half a pound as a cutout (or cutin? you don't say), as you say, it will only take a foot water overfill to keep the system off. But when you drain to the top of the sight glass it thinks that all is well and comes on again.

    As noted above, the question is -- why is it overfilled. Something is seriously wrong with the autofill system -- it shouldn't start to fill until the water level is down almost to the bottom of the sight glass. Unfortunately, since the autofill is linked to the low water cutoff on most boilers, this suggests that something is wrong with the low water cutoff, or may be (you don't know) which means that the boiler is unsafe to operate. Turn it off with the emergency switch and leave it off until someone finds and fixes the problem.

    Turning half the radiators off -- provided you have done it correctly (not with the valves at the inlet, unless you are positive they are steam tight -- which they almost never are) may save some energy. It will also mean that your boiler is now very much oversized, and may lead to some interesting misbehaviour when you get it running again.

    And I have to ask. Are the radiators which are off in parts of the building which can have air entering them from occupied areas? Simply closed doors won't do. If so,, keep a very close eye on humidity and condensation in those areas with the radiators off. That condensation may cause mold problems, and can -- and will -- cause serious and possibly catastrophic damage to books, plaster, musical instruments, paintings, fabrics... whatever. I've seen that happen, and been involved with restoration of buildings where it was done. Eye-wateringly expensive.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • nicksxvs
    nicksxvs Member Posts: 50
    edited November 2020
    with the level at the top of the site glass, as soon as i start to drain it the burner comes on. come to think of it. the burner comes on almost immediatetly when i open the drain lever at the bottom of the level guage, the level guage is what i call the black cast iron oddly shaped fitting, but when i drained it from the cock at the bottom of the boiler the burner took a minute before it kicked on. this tells me the level guage float is hungup and the water rushing thru it tricks it. i looked and could not see a low water shutoff.edit, when i turn the pressuretrol dial up to one pound the burner comes on.
  • Jamie Hall
    Jamie Hall Member Posts: 23,160
    Kindly reread my previous comment.

    Until you get that autofeeder and float and so on fixed, you also have a malfunctioning low water cutoff.

    That is very very dangerous. Turn the boiler off and leave it off until you get that fixed.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,452
    Sounds like the low water cutoff/feeder needs some work