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Sight glass explained

Hi all - just moved into a house with a steam boiler and I have no idea how it works. Forgive the naive questions that will inevitably follow.



For starters - can anyone give an explanation of what the sight glass is used for and what the values at the top and bottom should do? The system is a Weil-Mclain with an auto-feed for the water. The sight glass is about 3/4 full and both values are mostly open. I may have turned one of the values inadvertently and I am worried I screwed something up.



Thanks for any help!

Comments

  • BobC
    BobC Member Posts: 5,476
    sight glass

    The sight glass is to show you what the water level in the boiler is. the valves above and below the glass should be fully open (full CCW) so allow unrestricted flow. they are sut down only if you are replacing the sight glass tube.



    The level is usually somewhere around half full. Try to keep track of how often that auto water feeder is turning on, it shoud only happen once or twice a month.



    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
  • Aveeight
    Aveeight Member Posts: 29
    Dirty water

    Thanks again Bob.



    I've only noticed it add water once so far this winter so it seems to be ok.



    Sort of off topic but the water in it is filthy. I saw on another post from this site that you should drain or bleed the water once a month to remove sediment and build up. How do I do that? I'll get pictures tomorrow of the exact set up, but basically there is a big pipe sort of coming out of side at the top with a yellow handle but it is pretty much above the water line so I can't imagine that does anything. There is also a spigot at the bottom right corner that I really cant do anything with as its only about 1" off the ground. Aside from those 2 objects the only other release I have seen is the pressure release value which I am sure i shouldn't touch.
  • Rod
    Rod Posts: 2,067
    edited January 2011
    You need the Book!

    Hi- I was just recommending this to someone else. What you need to get is a book titled "We Got Steam Heat!" which is available on this website.

    http://www.heatinghelp.com/products/Books/5/61/We-Got-Steam-Heat-A-Homeowners-Guide-to-Peaceful-Coexistence

    It's written for the homeowner new to steam, it's easy, humorous reading, has lots of pictures and diagrams and in an evening or two of reading, you'll be light years ahead in your knowledge about your steam system.  Mine copy has paid for itself as least 100 times over.

    - Rod

    Edit : LOL- Sorry about that!  Same person!  Most of us (homeowners) were like yourself when we first found this site and this book and others of Dan's have really helped us find our way out of the dark.
  • BobC
    BobC Member Posts: 5,476
    Filthy water

    Dirty water in the sight glass does mean the boiler needs to be drained and refilled with clean water. The fact your mud leg  valve is frozen (lowest point in the boiler) tells me it's a long time since this was done. that valve will have to be freed up or replaced. I leave an old washing machine hose on mine so I can drain a couple of quarts into a bucket one a week or so. My boiler is up on 4" blocks so I have more clearance than you do.



    The large pipe with the yellow handle that is above the water line sounds like a skim port, I assume the end of that pipe is open or maybe has a cap on it? The skim port is used to clean the surface of the boiler water. You feed water into the boiler until it slowly trickles out of the skim port, for proper skimming you do this very slowly - a couple of hours to fill a five gallon bucket.



    With your mud leg temporarily out of commission you can use the skim port to drain some of that dirty water out. It won't work nearly as well as going through the mud leg but it's better than nothing.



    When you post the pictures tell us the make and model of your boiler. Is the water in the sight glass bouncing up and down a lot when the boiler is steaming?



    I second rod's advice on that book and I'll add a second title to get once you have digested that one - "The Lost Art of Steam Heat". Both are available from the SHOP menu of this site.



    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
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