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What does this valve do?

My thinking is that the pipe to the right was the cold supply to the coil. The pipe in the middle goes to the expansion tank. The valve between the two, although it does look like the ones installed to mix the water, I believe was the original fill valve. The pipe to the left, the one that ends in a ball valve, would have been the hot line from the coil.

I can't be sure, but at the bottom of the picture, it looks like a handle from a mixing valve!

It would be nice if he would post some more pics. showing where the pipes go!

Happy Thanksgiving everyone!



  • Tom Hopkins
    Tom Hopkins Member Posts: 539
    What does this valve do?

    I took a picture of the valves above my boiler. I keep the one open to the expansion tank only, the rest are shut.

    1. What does the valve in the middle of the "H" do? should it be open? I usually open it when I have the fill valve open to fill the ssytem

    2. Should the fill valve be open all the time? I'm thinking no, as I don't think I have an auto-fill valve installed, right?

    PS. ignore the domestic water pipe with the ball-valve on the end, I at least know what that goes to, nothing :)
  • Brad White
    Brad White Member Posts: 2,393
    Nearest I can figure, it is a

    valve of German manufacture, a "DasBlurrendiePhotograffen" valve, impossible to photograph without their "fokusin-attachmentgereit" und der "Flashen-Objekt".
    "If you do not know the answer, say, "I do not know the answer", and you will be correct!"

    -Ernie White, my Dad
  • Tom Hopkins
    Tom Hopkins Member Posts: 539

    sorry, picture is bad, poor lighting, I haven't gotten to the basement yet in rewiring the whole house project.

    The valve i'm asking about is the one that is on the cross-member between the fill line and the expansion tank line

  • Mike T., Swampeast MO
    Mike T., Swampeast MO Member Posts: 6,928

    Here's the photo brightened and sharpened. Must say that I don't understand the purpose of the valve in that horizontal connection between the two pipes.
  • Tom Hopkins
    Tom Hopkins Member Posts: 539

    Thanks Mike,

    Well if this provides any insight, there used to be a big old metal tank up between the rafters, and I replaced it with that new bladder expasnion tank, perhaps it had something to do with that metal tank?
  • Al Roethlisberger
    Al Roethlisberger Member Posts: 194
    Need more info, maybe a balancing valve

    Perhaps some sort of manual balancing valve between the supply/return on one of the loops(primary/secondary)?? It's hard to tell without further frame of reference.

    If you can take another photo showing more of the piping, and perhaps describe which pipes are supply/return and if there are any primary/secondary loops, etc.

    The fact you can see where the expansion tank is hooked in may help a bit, but still hard to be certain without further context and photos.

    Just a DIY'er trying to learn, and improve and maintain his converted ca 1929 overhead gravity hot water system since there is no one local that can.
  • Scott Larabee
    Scott Larabee Member Posts: 28

    Does the domestic pipe with the ball valve on the end go to a coil in the boiler?

    I think, if that is the case, that the pipe with the fill valve leads to the other side of the coil, and the valve in the "H" is the original fill valve.

    Just a guess, as the photo doesn't show enough of the piping!

  • bill_71
    bill_71 Member Posts: 46

    oh i know what that valve is for.......thats one of those fancy new valves that when you turn it clockwise it shuts somethin off and when you turn it the other way it opens and lets stuff through it. its a shame we can't see what those copper pipes are attached to though
  • Rich Kontny_3
    Rich Kontny_3 Member Posts: 562

    the hell out of me! Workmanship and ball valve to nowhere(on up tp 200* hydronic system.
  • Leo
    Leo Member Posts: 767
    If it goes to

    If it goes to the tankless coil it was used in place of a mixing valve years ago. No longer legal here.

  • Robert O'Brien
    Robert O'Brien Member Posts: 3,269

    can see a RA117 in the background of that pic.At the very least that should be upgraded to a cad cell primary and with oil @$3.50/gallon any unit using a stack relay should be headed for retirement ASAP

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  • Right,

    We need to see where the piping goes at the bottom of the pic. Scary is a great word for sure...

    None of that looks right...
  • What Leo said...

    I'm guessing its a fixe dpostion mixing valve. As he said, illegal as hell. Lots of liability hung on that valve.

    One pipes is darker than the other (cold) and the other is real shiny (hot, no condensate to oxidize pipe).

  • chris_95
    chris_95 Member Posts: 47

    Sorry guys, I just found this thread again, the email notification didnt work and I never saw any of these replies. The DHW was disconnected, and yes it looks like a real shoddy job... some idiot who also installed the water heater installed this ball valve...the guy jammed a mis-matched breaker in my breaker panel too I ended up replacing when I bought the house...and he did a scary job of running the romex overtop the rafters (code violation) which I also had to fix....

    I will take some more pictures and post them tommorow of the rest of the piping, etc..

    There is a mixing valve below the other valves that you can see in the picture.

    That is a 117 stack mounted relay, I just replaced it, I had an spare when I bought the house, and the one installed was in bad shape. I am looking at replacing the whole boiler next year, so it just has to get me thru the season... do you think that's why I'm using so much oil? I'm using a TON.

    I am having trouble with air trapped in my system, so I decided to open the valve... well needless to say, the next time my boiler ran, I heard some really loud noises , I think it may have been the diaphram in the expansion tank, but it was really loud, in fact I hit the cut-off switch on the way down the stairs it scared me so much. ... So I looked at the gauge, and there was no pressure, ouch! so I quickly added some water to the ssytem and brought it abck up to about 15 psi.... I ran the circulator manually to try and see if some more air would come out, but it didn' I fired everything back up, and this time I closed the mystery valve... I'm not sure if the air finally just went into my expansion tank, or something went really wrong, but I probably don't want my pressure to drop to 0 when I'm not home... would opening that valve have caused that?? Do you think it was just trapped air escaping I heard? It was very loud.
  • Timco
    Timco Member Posts: 3,025

    More pictures, please...Include all near boiler piping & the vent.

    Just a guy running some pipes.
  • chris_95
    chris_95 Member Posts: 47
    here's the pictures

    Here are the pictures... oddly enough again, I came home from work and found the pressure at 0, but I just cracked open the fill valve (both) for a second, and it popped back to 20 right away.... bad gauge or something maybe?? Right now I noticed it's at about 15...but I'm guessing it might end up at 0 again tommorow... all I know is the first time it went to 0 , it made some funky noises I have never heard before...

  • I can't tell for sure, but it looks like your expansion tank is connected to the domestic water. The 3/4" copper pipes that go into the top of the boiler are connected to a domestic coil. The expansion tank should be connected to the heating pipes. Again, I can't see for sure- but that's what it looks like.

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  • chris_95
    chris_95 Member Posts: 47

    oops, there used to be an old long metal tank in the rafters that was connected to this line, and I thought it was an expansion tank, so I replaced it with this new tank. Was this actually an expansion tank for the DHW, and by replacing it, I did nothing, since I'm not using the DHW? whoops.
  • chris_95
    chris_95 Member Posts: 47

    well actually on 2nd thought, I have to open the valve between the 2 pipes to fill the system, so wouldn't that mean it is connected to the heating side, since the pipe that it is connected to fills the boiler?
  • JIM W.
    JIM W. Member Posts: 16

    Who ever did this piping job should be hung do you realize that you domestic coil piping that goes thru the mixing valve leads to no where. That end of the 1/2" ball valve is the supply to the domestic hot water line for the whole house. The expansionn tank should be tie into the heating system. If I were you I get this fixed as soon as possible By the way how were getting domestic hot water to your sinks, etc.
  • Weezbo
    Weezbo Member Posts: 6,232
    this is the first time i saw this post...

    unless your boilers domestic coil is ruptured and there is an anti back flow suppression valve and fast fill somewhere else in the field..... the extrol tank cannot communicate with the boiler at all. if you do have a rupture in the coil And the tank is water logged , a very dangerous situation is at the threshold of your home.

    get someone to re pipe the thing before you become a statistic. i would lose the burner as well. have the boiler cleaned first ...if you test the combustion on the boiler first the differences will become apparent to what i am saying ...
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