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Hot water system hammering

Bill Gripp
Bill Gripp Member Posts: 4
in THE MAIN WALL
Problem with new system hammering. Installed a Weil McLain CGI 7 with seven Honeywell zone valves (one is a full port valve for domestic hot water,the rest are normal zone valves) If more than one valve is calling for heat and a zone starts to close the system hammers. If its two or all seven running,if one valve closes,it hammers. If I remove one spring from zonevavles the system is quiet,but heat seaks by zones that are not calling. System is pumping away and zones are on the supply. The manifold is 1-1/4" with 3/4" tees to each zone. Any ideas, thanks. Oh to make matters worse the cliant is a know it all architect.

Comments

  • Al Corelli - Agix Associates
    Al Corelli - Agix Associates Member Posts: 52


    Maybe a pressure differential valve would help.

    I hate zone valves...
  • kevin coppinger_4
    kevin coppinger_4 Member Posts: 2,124
    as AL said....

    the diff. pressure bypass valve would work or a straight by pass w/ a ball valve partially opened to give the pressure jump some place to go. This "problem" is why if using zone valves and pumping away the ZV should be placed on the returns....kpc

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  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,600
    You're the first!

    Banging Zone Valves

    It pays to wander off the Wall.
    Retired and loving it.
  • Richard_4
    Richard_4 Member Posts: 40


    I dont mean to insulte anyones smarts, but are the zone valves installed with the arrow going with the direction of flow?
  • Steve_35
    Steve_35 Member Posts: 546


    The problem with motorized valves is they close too darned fast. The circ is running. More than one zone is calling. The water is hustling through the pipes The call for heat ends at one zone and it SLAMS shut.

    When we run into this we change them over to Taco zone valves. They're slow to open and slow to close. About 45-60 seconds. And very quiet. We install a lot of them.
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