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Filling steam boiler. Is this right?

Rob30 Member Posts: 8
Hello all. Great site here. I thought it was time to drain my very old Del-Ray steam boiler and add in new water. I turned it off and drained it completely using the drain valve. I let it sit and cool down for a few hours, then went to fill it. When I was filling it, some pipes on the opposite side must have filled with water because water began to come out of these air-bleed looking valves at the tops of the pipes. So I used the drain valve on the bottom of those pipes to drain that water. This did not lower the water level in the sight glass. So I was able to fill the boiler to the correct level on the sight glass, but had to drain water out from the other pipes in the back.

Did I do this right? I attached a pic that will hopefully make it easier to understand what I mean. I havent turned on the boiler yet. Want to make sure I did this right. Any advice would be appreciated. Thank you.


  • crash2009
    crash2009 Member Posts: 1,484
    Something doesn't sound right.

     Can we see a picture of exactly where the water line connects?  and also the valve you use to turn on the water with.
  • Rob30
    Rob30 Member Posts: 8
    Some more pics

    Sure. Here are some more pics. The first pic shows where I drained the boiler, then the valve I used to fill it, to the marking on the sight glass.

    The second pic shows the other two sides of the boiler. I marked where the two air bleeders are on top of the two pipes, as well as the drain. Like I said, water came out of these bleeders when I was filling the boiler. Once the sight glass showed the correct amount of water, I used the valve in the second pic to drain the water from those pipes.

    I'm not really sure what else to take pics of, so please let me know if I can help more with that. Thanks again.
  • Patrick_North
    Patrick_North Member Posts: 249
    Plugged sightglass?

    It could be that your sight glass is plugged and therefore isn't showing the true water level in the boiler.

    Water could be expected to come out of these vents if you simply overfilled your boiler until water entered the steam mains. These vents would simply be the first available exit point for the rising water. If your sightglass was mostly plugged up it might take a while for the true water level to register- if it does at all.

    The petcock valves on a sightglass are often not of the best quality- some installers replace them with better valves. Removing the sightglass and giving them a good cleaning is not terribly difficult, given care, and may be worth a try in this case.

    This is also a good reminder to blow down your boiler regularly. Might be time for an annual checkup from a local boiler pro. And consider updgrading (read: upsizing!) your main vents while you're at it.

    Good luck,

  • crash2009
    crash2009 Member Posts: 1,484
    I am not a pro, but I will take a guess

    Looks like the fresh water input is connected directly to the bottom of the boiler.  You filled it up, the sight glass was slow to register a reading(?), the water continued to fill until the main vents shot out water.  My best guess is one of the sight glass tappings are nearly if not completely plugged.
  • Rob30
    Rob30 Member Posts: 8
    Ok...so what now?

    I think you guys are right. The sight glass was slow to fill. I may call someone to clean it. I really don't want to break it and everything on this system is too old to mess around with. In the second pic where those verticle pipes are (where water was coming out from the tops)... was I right to use the valve at the bottom to drain out the water from the pipes? Those pipes should not have water in them, correct?
  • Paul Fredricks_3
    Paul Fredricks_3 Member Posts: 1,557
    One problem

    I don't think the gauge glass is plugged. If it is it's most likely just the bottom half where the water sits. The top would most likely not be plugged. Once the water level reached that point it would spill over and fill the glass.

    It seems more likely that the return tapping in the boiler is plugged. Feed water would find it much easier to go up and over the Hartford Loop and up to the vents.

    It looks like there is a drain valve in the back of the boiler where the fresh water goes in. If this valve is removed it looks like a straight shot into the boiler. I'd use some sort of tool to reach in there and clear out whatever is clogging it.

    Just my opinion.
  • Rob30
    Rob30 Member Posts: 8
    few things to try

    Thanks for the reply. I will see if I can unclog it. As far as the sight glass goes, it could be partially clogged, or maybe I just filled the system too fast and water came out from those top vents before the sight glass had time to show an accurate reading (?)

    Again, the piping in the pic below (those 2 vertical pipes parallel to each other and where the Hartford Loop is) should NOT have water in them, right? So using the drain valve below them (in the same pic) to drain the water out was the right thing to do?

    Now I just need to make sure the water in the boiler is the correct amount and see if there are clogs. Does this sound right? Thanks again for the help.
  • Paul Fredricks_3
    Paul Fredricks_3 Member Posts: 1,557

    There will be water in every pipe up to the level in the gauge glass. So those two pipes should have water part way up, but the water should never get to the vents, even if you are filling it fast. That's why I think the bottom boiler tapping is plugged.
  • Rob30
    Rob30 Member Posts: 8
    That explains it

    Thanks for the reply. The level in the sight glass was a little bit lower this morning than it was last night. That must be because I drained water from those pipes ( I thought they had to be free of water). Now I know that isn't so. I will check for that clog, maybe attempt to remove and clean the sight glass, fill then hope for the best. I'll let you know how it went.

    Thanks again.
  • 04090
    04090 Member Posts: 142

    Did you mess with the valves above or below the glass?  They both need to be open.  Maybe worth checking.
  • Rob30
    Rob30 Member Posts: 8

    Yes, they are both open. Thank you :)
  • Rob30
    Rob30 Member Posts: 8

    Well everything seems fine now. I was too afraid to remove and clean the sight glass. I'll have to remove the drain valve and check for a clog another time. I really believe there is some kind of clog at the sight glass too though. But I was able to fill the boiler and sort of "guess-timate" a good water level. I even let it sit for an hour or two to make sure the water would settle and the sight glass would eventually show an accurate reading.

    The boiler has been on for a few hours now and all the radiators are nice and hot. There is some hissing on some of them, but no steam coming out the radiator vents. Just air.

    I took a pic of a larger air vent on one of the bigger pipes, which is on the other end of the basement away from the boiler. There is a good amount of air coming from this. Is this normal? This pipe goes back to the pipe I marked in the second pic.

    Thanks again guys.

    ps - that's not poop on the pipe. It's just old and rusty ;) lol
  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,787
    That's not just air.

    It's normal for air to escape from the vents (that's what they're for), but they should close the instant the steam reaches them. It looks like that's not happening. Aside from all that rust, I see water droplets on the material attached to the ceiling, which was probably put there to keep the steam from making the floor sag. Live steam can really do a lot of damage, so you should replace that vent. Probably a Gorton #1 will do.
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
  • Rob30
    Rob30 Member Posts: 8
    Will Do

    Thanks for the advice. I will definitely replace that vent. The material on the ceiling was put there as insulation. It was part of this coverage we got where a crew did some work to this home to better insulate and weather proof it. But I agree.. a new vent is in order. Actually...a whole new system is in order :) That's my hope for this summer, before next heating season.

    I'd like to thank you all for your help with this. I wish you all the best.
    THESICILIANPR Member Posts: 1

    MY BOILER ISNT RUNNING PROBABLY BECAUSE THERE ISNT ENOUGH WATER IN IT. The valve below the sight glass is leaking , could that cause the water level to be incorrect? When I closer the lower valve it shows no water in the glass, even with the top one open. Any ideas? I don't want to flood the system by adding too much water.

    Thank you
  • Mark N
    Mark N Member Posts: 1,094
    edited December 2013
    Boiler Water Level

    You should have started a new thread. The bottom valve of the gauge glass needs to be open to correctly see the level of water in the boiler. If it leaking get it fixed. If you don't see any water in the gauge glass I would assume the level of the water is low and the LWCO has the boiler cut out. Have a professional come in a fix.
  • that boiler

    Other comments do make sense.. however, that boiler is incorrectly piped for steam.. when comes to replacing it.. make sure you ask a lot of questions, also great books here for homeowner like you.. the steamy deal..
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