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Water pouring out of steam vent 2x+ a day.

Hi Everyone - hoping for some guidance here.

A few weeks ago I woke up to a large brown puddle on the living room floor, water originated from a 3rd floor radiator. It's been pretty consistent since (pic below).

Boiler is about 5 Years old
The Pressuretrol is set at 1.5 with a .5 diff
Last time I checked the internal pressure was running just under 3psi.
This Radiator is on its own line, 3 years ago I had issues originally with it not heating up but it is now working great since the fix (more venting).
No other issues with the other radiators
Hoffman Steamvent which I did clean with vinagar, seemed to help a bit.

December gas 2020 usage was a little less than 2019, my January 2021 bill was 21% over Jan 2020. Temps were about the same. We were home more this January working from home but Temps weren't that far off if at all. I was expecting an increase but not that much.

I read through a few of the posts read that skimming or flushing the boiler might help solve all of this. Wondering if this is a good first step or you would recommend something else. This boiler does not have skimming port, will flushing this make any difference?

Here's a quick snap, I am seeing this level 2x a day. Everyone once in a while it fills close to the top. I can't find any consistency to when it happens.

I appreciate everyone's help with this.


  • JohnNY
    JohnNY Member Posts: 3,231
    A frequent cause of this is partially/clogged return pipes.
    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Consulting & Troubleshooting
    Heating in NYC or NJ.
  • Jamie Hall
    Jamie Hall Member Posts: 23,323
    Pressure is too high -- bring it down to cutting out at no more than 2; 1.7 is better.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • neilc
    neilc Member Posts: 2,703
    known to beat dead horses
  • ethicalpaul
    ethicalpaul Member Posts: 5,704
    That looks like boiler water. If it were pressure driving it all the way to the 3rd floor then surely the first and second floor radiators would be spraying first.

    I suggest the single line running up to this 3rd floor radiator is not piped well and the boiler water is carrying all the way up.

    can we see a photo of the near boiler piping especially showing the line that runs up to this radiator?
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
  • MilanD
    MilanD Member Posts: 1,160
    edited February 2021
    A few questions:

    1. Is the vent closing when radiator is hot? 
    2. Have you observed when in the heating cycle is the vent leaking?
    3. You said your pressure is set at 2 psi, and that your gauge shows 3 psi. Is this a 30 psi gauge? (If so, your pressure may in fact be way higher than 3 psi which may cause a vent to fail. Get a 3 psi gauge for accurate reading. Also, check the pigtail or piping setup around the pressuretrol for obstruction.)
    4. Did you try swapping this vent with another and see if the problem is cured with a new vent?
    5. Your higher gas usage may in fact be connected to your 3 psi pressure observation. Your pressuretrol may either not be "seeing" the actual system pressure (#3 point above), or may have broke or became miscalibrated, and thus your burners may be needlessly running longer cycles and higher pressures, which wastes fuel.
    6. Do you do a nightly setback in temperature, and by how many degrees?
    7. Where on the main is the riser to this radiator? Closer to the boiler, farther? Is there an elbow just before or after its takeoff?

    My $$ would be on your vent being in fact broken, caused by high operaring pressure.
  • gerry gill
    gerry gill Member Posts: 3,078
    I’m wondering if there is a piping problem.
    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

    EBEBRATT-Ed Member Posts: 15,540
    I would clean the pigtail under the pressure control. If the vent didn't spit before what changed? You may be running more pressure with a clogged pigtail. And make sure your steam gauge works you may want to add a low pressure gauge.

    You want to run 2 psi max. the lower the pressure you run the better
  • matthewb84
    matthewb84 Member Posts: 27
    Thanks everyone, my guess is the pigtail as well. I will be looking at that either today or tomorrow.

    Question on this and to confirm the way I remove won't break anything. I have a Honeywell as seen below, model might be off but same look and bottom.

    I watched a video where the mechanic removed the unit from the base and then unscrewed the pigtail from there. Is this ok? Removing the base opens access to the piston but doesn't affect anything else.

    Looks like the easiest way to do this on my system.

    Would love input from the group.

  • ethicalpaul
    ethicalpaul Member Posts: 5,704
    edited February 2021
    No, don't remove the bottom. You risk pieces flying away and getting lost. Just disconnect the two wires and label them (or remember them). It doesn't matter which wire is which, just label the two of them "pressuretrol" (on paper, or in your mind). And make a note or photo of where they were attached.

    If you want it easier to remove in the future, plumb a union in underneath it.
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
  • matthewb84
    matthewb84 Member Posts: 27
    edited February 2021
    Hi Everyone,

    Quick update, I went to remove the Pressuretrol and decided to adjust and run a few cycles to see exactly what was happening.

    Before adjusting Pressuretrol boiler was cutting off just under 3psi on the 30psi gauge.

    I made several adjustments where the boiler now cuts of around 2.1 and refires just as it passes under the 1psi mark on the gauge. You can see in the image below that the pressuretrol markings are not exact science, which I gathered from reading several other posts.

    Can I now assume this is working and my not need to be cleaned?

    A second question, my water mark is up REAL high. Is this a problem caused by the high pressure cut off? Should I bother draining this a bit? The Water does look clear but when the boiler fires it does get dirty.

    Thank you for everyone's help so far.

  • clammy
    clammy Member Posts: 3,112
    If that’s your normal water level there a issue lower it half the sight glass having a higher then normal water level in the boiler usually causes issues .Lower the water level . There also seem to be a bit of crude in the glass this my be a indication that your boiler needs to be flushed and cleaned there should not be crud in the sight glass. The water appear to be clear but does it turn dirty s the boiler is steaming if so the boiler needs to be cleaned I usually fill and flush a little bit then drain the boiler ,remove plugs on boilers inlets and use a wanding tool to wand the boiler out to flush all the lose crap ,re install plugs fill and flush ,fire her up and skim until clear ,close the skim tapping and steam her up . Sight glass should be clear and no surging while boiler steaming . You may have a little rust in the site glass at first but it will settle down if it’s surging and the boilers clean then it possibly near boiler piping related due to the boiler producing wet steam usually from under sized headers and bad piping practices aside from all the regular culprits that cause issues . I also think that trying to vinegar soak a vent is useless just buy a new vent preferable a quality one like a gorton . I also think as others have said the washer has come off and is not letting the radiator drain . If the supply for the radiator is piped off the near boiler piping it may need a drip to help drain the condensate separately into the return espically if the radiator is on ethe second floor peace and good luck clammy
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating
  • HarryL
    HarryL Member Posts: 59
    Have you checked the union at the radiator? I don't know if that could account for the amount of water you are seeing but a fair amount of condensate can leak there.

    Home owner, 1927 2-story, single family
    1 pipe Burnham IN4I, Boston area