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What is this and why

Discussion in 'Commercial' started by otto, Aug 11, 2017 at 8:35 AM.

  1. otto

    otto Bakery Chef

    Messages:
    19,782
    Location:
    in a van down by the river
    Not the mixing valve, the long valve with the taps.
     
  2. otto

    otto Bakery Chef

    Messages:
    19,782
    Location:
    in a van down by the river
  3. otto

    otto Bakery Chef

    Messages:
    19,782
    Location:
    in a van down by the river
  4. otto

    otto Bakery Chef

    Messages:
    19,782
    Location:
    in a van down by the river
  5. otto

    otto Bakery Chef

    Messages:
    19,782
    Location:
    in a van down by the river
  6. frozensolid

    frozensolid Psychologist's Dream

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    11,978
    Location:
    Earth
    To me it looks like it's keeping supply pressure higher than return pressure but with restricting flow. Just a guess.

    Why I am not sure about some kind of bypass?
     
  7. pecmsg

    pecmsg Junior my ASS

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    Eastern LI
  8. frozensolid

    frozensolid Psychologist's Dream

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    Location:
    Earth
    We don't do many boilers in the sunshine so school me. Could they be using that to keep the boiler fired during low load demand. To keep the cold water sandwich effect from occuring?
     
  9. otto

    otto Bakery Chef

    Messages:
    19,782
    Location:
    in a van down by the river
    So still not sure about the why but, it did make the rattling noise today so it's getting a new one. Also a bad 6" check and shut off valve on one of the primary pumps. There are so many scenarios that this device can apply to. I am not 100% sure why it is in there, perhaps to limit the flow through the heat exchanger or to prevent excessive bypass from supply to return when the heat exchanger is satisfied.
    It rattles loudly when the 3 way valve goes to anything over 50% call for heat. You can hear it through all of the other piping it's so loud.
     
  10. Ballvalve79

    Ballvalve79 It's only fire what could go wrong

    Messages:
    179
    Location:
    Northwest PA
    It's definitely a flow control. I would bet it's rattling because it's stuck internally something in there moves to regulate flow whatever that part is is bound up or worn making it rattle.
     
  11. Snoring Beagle

    Snoring Beagle Need Little - Want Less - Love More

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    11,099
    Zman likes this.
  12. Zman

    Zman Hanging by a Thread

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    The "I know a Guy" State
    Just Delt with one of these on a Florida H.P., wasn't exactly sure what it was or how to test.I am now! Thanks! :thumb:. Had poor flow,locking out on High Pressure.Pulled the cartridge,looked a little beat up,have to replace. And 4 what's its Worth,in my Boiler experience,when ever I had a flow valve that was noisy,it was usually because of low pressure.
     
  13. Snoring Beagle

    Snoring Beagle Need Little - Want Less - Love More

    Messages:
    11,099
    I was working at a cop shop when I ran across every baseboard used for perimeter heat had a Griswald type 3/4" auto flow and 2 way valves for control. It was the valves that would groan when closing. Could hear the groaning loudly all thru the area affected.
    Sounds like a toilet bowl float valve whining just before it closed. Usually you can open the supply valve wider to get that to stop on a toilet it will shut with more force the faster the float moves.

    Them auto valves get dirty too
     
    Last edited: Aug 12, 2017 at 3:47 PM
  14. oroy54

    oroy54 New Member

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    Victoria, Texas
  15. knave

    knave Out for a rip

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    Location:
    Out for a rip
    When it gets replaced I would appreciate a dissecting with pics!!