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Help with Zone Valve and purge valve installation

gpettit
gpettit Member Posts: 6
I have a 2 zone Hydronics system. Moving into the house I discovered both zone valves disconnected (no wires) and manually set to the open position so system is acting like a one zone system. I also noticed their is no purge valve or cut off valve, I got to have those.. right? I would like to replace the zone valves and install purge and cut off valves. My questions are ( NOTE: old inoperable zone valves are on the return side):

Does it matters the order I install these? Meaning should the cut off be in front of the zone valve, should they both be in front or behind the purge valve?? Example I was thinking (return from loop (zone1) --> purge valve --> shutoff valve -->zone valve) but what do I know, hence why I need guidance - thanks.

Or do I put the purge valve and cutoff valve after the zone valve at the point where the two loops come back together in one pipe so there is only one if each??

Thank you all for any guidance.
-George

wcs5050

Comments

  • Page 48 of Dan Holohan's book, "Pumping Away" shows the setup that I've used for years.

    If you get a copy, there will be lots of useful information for you as the owner of a hydronic heating system.

    You can find it here:

    http://astore.amazon.com/heatinghelp-20/detail/0974396087
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • hot_rod
    hot_rod Member Posts: 22,022
    edited January 2017
    Here is an example of a common way to pipe.
    Zone valves on the supply after the pump prevent unwanted ghost flow.
    The purge valve on the return is often a valve like this.


    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • gpettit
    gpettit Member Posts: 6
    First thank you both for taking time and replying to my post.
    Thanks for the book recommendation Alan, I'll be getting that for sure.
    Hotrod - I understand my setup does not match your common way to pipe as my zone valve are on the return. Your diagram shows zone valves on the supply side so not sure if yours saying I should redo my piping?? But, i think, it also show purge valve then ball valve on the return side on what appears to be after where the two zones come back together to a single pipe is that what your saying I should do? Also your second picture is of what appears to be a ball valve and purge valve combo deal, that is awesome, I had no idea that was even a thing. Here is a pic of my setup in case it helps the discussion.

  • hot_rod
    hot_rod Member Posts: 22,022
    Typically hot supply is out the top of the boiler, return on the bottom? Also the air purger is also installed at the supply out of the boiler. I'd guess the pump is pushing into the bottom, return of the boiler?

    Is your drawing correct or am I hallucinating?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • BornForDying
    BornForDying Member Posts: 40
    > @hot rod said:
    > Typically hot supply is out the top of the boiler, return on the bottom? Also the air purger is also installed at the supply out of the boiler. I'd guess the pump is pushing into the bottom, return of the boiler?
    >
    > Is your drawing correct or am I hallucinating?

    +1 for verifying water flow direction. If the drawing is correct, maybe a replacement circulator was installed incorrectly.
  • gpettit
    gpettit Member Posts: 6
    wow... well I would believe you over me!! the drawing is right as far as where things are... the arrows on the other hand could be totally wrong... very sorry... I probably steered this thing totally wrong... reason why I thought this direction was when I had a tech here he put his hands on the pipes just below the zone valves and called them return lines...ha... crap... so looked at things closer the circulator pump has an arrow on it... it points up but that would mean the bottom is the out or hot supply side. However there are also arrows on the zone valves point down or that the flow is going out the top as you describe. WTH.
  • gpettit
    gpettit Member Posts: 6
    it would make a lot more sense if it is as you describe. So this would mean I would need to put this ball & drain valve under the circulator pump, correct?? that sucker looks to be a 1 1/4 pipe.
  • BornForDying
    BornForDying Member Posts: 40
    So if I'm understanding you correctly, the flow direction arrows on the circulator and zones valves are not facing the same direction?

    Posting some pictures of the boiler and piping would be great.
  • hot_rod
    hot_rod Member Posts: 22,022
    From what I see you are correct, the pump is flowing out of the bottom of the boiler, returning to the top.

    Probably been working like this for how many years?

    The best way would be a bit of a repipe. I'd reverse the loop pump out the top of the boiler, zone valves after the pump, return to the bottom with a purge valve there.

    So boiler supply out, air purger and expansion tank next, pump downstream of the air purger, zone valves, through system, return to bottom. Just like the drawing a few posts above.

    Don't know that I have ever seen a zone valve with a clear plastic cover? I'll send you two Caleffi Z-one valves, you send me that old valve.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • BornForDying
    BornForDying Member Posts: 40
    > @hot rod said:
    > From what I see you are correct, the pump is flowing out of the bottom of the boiler, returning to the top.
    >
    > Probably been working like this for how many years?
    >
    > The best way would be a bit of a repipe. I'd reverse the loop pump out the top of the boiler, zone valves after the pump, return to the bottom with a purge valve there.
    >
    > So boiler supply out, air purger and expansion tank next, pump downstream of the air purger, zone valves, through system, return to bottom. Just like the drawing a few posts above.
    >
    > Don't know that I have ever seen a zone valve with a clear plastic cover? I'll send you two Caleffi Z-one valves, you send me that old valve.

    I agree this is the best thing to do. Pumping away from the expansion tank is always best.

    Another solution that might work:

    I think you could also replace the threaded coupler on top of the boiler with a full port ball valve.

    This would allow you to shut that ball valve, then purge each zone through the drain below the circulator using the zone valves to isolate each zone.

    Also swap the circulator so it's pumping in the correct direction.
  • hot_rod
    hot_rod Member Posts: 22,022
    How old is the system? I'd guess you are on borrowed time with those thermo actuated zone valves.
    If budget allows now, or come spring, a repipe would solve a bunch of issues.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    BornForDying
  • gpettit
    gpettit Member Posts: 6
    Thank you both very much for your insight and recommendations. I learned a ton here and now I understand the most correct thing to do is repipe so that I'm pumping away from the expansion tank and to get things flowing in the right direction. I think I'll be waiting til spring for this as I'm sure it will take longer then my wife and kids can tolerate during the winter :-). Bob, when I get these plastic cover zone valves off, I'd be happy to send them to you Sir. It's the least I can do for all the time you spent on this discussion. I'll just need an address. Here's my email if you prefer getting it to me that way. 4gpettit@gmail.com
    BornForDying
  • billtwocase
    billtwocase Member Posts: 2,385
    Bob, I am not sure what brand zone valve that is, but Neucom/Brenco were clear plastic. Had many years ago, and still have a few new ones in stock.

  • HVACNUT
    HVACNUT Member Posts: 5,804
    Little late for a comment but all you really need to do (most cost effective)
    is to flip the circ so the arrow is pointing down. You can change the position of the motor by removing the 4 screws bolted to the body and turn it 180 degrees.
    Still no way to purge though.
    Maybe there's isolation valves in the crawl space?
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,453
    Just curious. How does the building heat now with the disconnected zone valves?? Is it comfortable?? Possibly there is a reason other than failed zone valves for the current operation.