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Rattling flow control valve

Steve_210
Steve_210 Member Posts: 646

Installed about 10 years ago I know there’s a reason but I can’t remember why.
I backed it off enough so the noise would stop but maybe nowI will get Some gravity circulation.

Comments

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,983
    If it rattles you have air going through it
  • hot_rod
    hot_rod Member Posts: 22,700
    check whatever air removal device you have. Purger float vents plug or get stuck after time.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Steve_210
    Steve_210 Member Posts: 646
    OK thanks there’s a Spirovent there I will check
  • JUGHNE
    JUGHNE Member Posts: 11,175
    Hot Rod & Ed, do they ever rattle because of low water flow not lifting the weight?
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 8,319
    edited December 2022
    JUGHNE said:

    Hot Rod & Ed, do they ever rattle because of low water flow not lifting the weight?

    Mostly air related. The air does not have the same specific gravity as the water, so the air flow going by the valve allows the weighted valve component drop. Think of this like a saw blade pushing up on the metal floating valve actuator. Bubbles are like the low spot of the saw blade, the water is like the high points of the blade. If you have all air, the valve will not open very much (only enough for the air to pass), if you have all water flowing, the valve will not close.

    Get rid if the air and the noise will stop.

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • hot_rod
    hot_rod Member Posts: 22,700
    Yes lack of flow could also cause the rattle. Open the Spiro at the seam and see what the screen inside looks like. They can act as both an air purger and a Y strainer.

    Without the Y pattern😆
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    EdTheHeaterMan
  • The Steam Whisperer
    The Steam Whisperer Member Posts: 1,233
    Also, they will rattle if piped too close to a tee or 90. You end up with turbulent flow.
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • Steve_210
    Steve_210 Member Posts: 646
    Over 10 years old I backed off the flow control valve a few turns and noise stopped it was late at night I need to go back for a boiler service
    I have seen that issue with turbulent flow