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Thread: Unknown Part

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    Unknown Part

    Can someone tell me what this piece is, I believe it is on the auto fill line, 3/4" PVC piping


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    benavidescj's Avatar
    Join Date
    Apr 2010
    Fleming Island, FL

    Re: Unknown Part

    It is a backflow preventer. Keeps water from flowing in the opposite direction. Usually find these on irrigation systems between the meter and the start of the system to keep water from flowing back into the city water system.
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    Re: Unknown Part

    Thank you very much! It looks slightly more complicated than some of the backflow valves i have seen in the past. What can I replace it with and do I need to involve the city if it is located at a hotel?

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    Ohm_Boy's Avatar
    Join Date
    May 2007
    Orlando, FL

    Re: Unknown Part

    Usually, your city water department will have all the info you need on that.
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    Join Date
    Dec 2009
    Central Massachusetts

    Re: Unknown Part

    Why do you want to replace it?
    14,000 gallon IG, Vinyl. Hayward 3/4 hp superpump, Penatair IC40 SWCG, Pentair automation, Hayward sand filter, Aqua Comfort heat pump, Hayward 400k Lo-Nox LP heater.

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    Re: Unknown Part

    it is leaking, i can find double backflow preventers but what is the piece that is pointing downward?

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    In the Industry

    Join Date
    Mar 2011

    Re: Unknown Part

    Quote Originally Posted by JoMain
    it is leaking, i can find double backflow preventers but what is the piece that is pointing downward?
    Watts call that a reduced pressure "zone assembly"

    Many municipalities require them because they are more expensive than a standard double check valve

    The piece on the bottom is calls an "air gap" which isnt needed if its just draining on the floor like it appears to be doing.
    20X40 30,000 gallon gunite pool

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