Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 3 of 3

Thread: What do I have in my Main Pool Drain

  1. Back To Top    #1

    Join Date
    May 2016
    Location
    Charlottesville, VA
    Posts
    6

    What do I have in my Main Pool Drain

    We're installing a new liner and have had some rain and water behind the liner. We're wondering if we have the 20.00 gizmo in the drain that will auto pump the water out once it gets more full. It's dry now so things have improved and we did pump a lot of water out from behind the liner. Looking good. Just curious. We've never had floating liner in our pool for 6 years.

    I attempted to take a photo through all the water. Not a great shot. Can anyone tell me what is in my drain?
    Attached Images Attached Images
    In ground, liner, 16 x 32, 23K, Sand Filter, Old install, date unknown

  2. Back To Top    #2
    JoyfulNoise's Avatar
    Join Date
    May 2015
    Location
    Tucson, AZ
    Posts
    11,620

    Re: What do I have in my Main Pool Drain

    Looks like a hydrostatic valve. They pop open when the water pressure under the pool exceeds the pressure of water inside the pool. They are designed to keep your pool from popping out of the ground if you drain them too much. When people do drain pools, they are usually opened to allow the water from underneath the pool to be pumped out to keep the pressure balanced.

    Just leave it alone and put the cover back on the main drain.
    Matt
    16k IG PebbleTec pool, 650gal spa, spillway and waterfall, 3HP IntelliFlo VS / 1.5HP WhisperFlo, Pentair QuadDE-100 filter, IC40 SWCG, MasterTemp 400k BTU/hr NG heater, KreepyKrauly suction-side cleaner Dolphin S300i robot, EasyTouch controls, city water, K-1001, K-2006 and K-1766 test kits, Mannitol test for borates

  3. Back To Top    #3

    Join Date
    May 2016
    Location
    Charlottesville, VA
    Posts
    6

    Re: What do I have in my Main Pool Drain

    I am so happy to hear this - my understanding is that once 4' deep of water (enough pressure) it will remove the ground water behind the liner automatically? Which explains why we never had an issue until we drained the pool and popped in the new liner (this was when the deep end was only 1/2 full) ---

    THANK YOU!
    In ground, liner, 16 x 32, 23K, Sand Filter, Old install, date unknown

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •