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Thread: A lot has been fixed but still losing pressure...

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    Question A lot has been fixed but still losing pressure...

    Please forgive the long story...

    We have a 20 x 40 inground DE pool. There are two skimmers and one main floor drain. We installed the pool 19 years ago. Two years ago after losing water and having no pressure we replaced all the supply lines from the two skimmers and made the independent. They were previously joined by a Y connection. We had found that inferior flexible piping had been used and were crushed and cracked over time. We also changed the lining, filter and pump. The pump was upgraded from a 1 1/2 to 2 hp. The main drain seemed fine and was left alone.

    For a year and a half all went well then end of last year the pump basket started collecting air. This happened after a half hour of great pressure and flow. Please be aware that since we have three independent supplies and two independent returns we closed each in every combination to see if it a particular line causing trouble. But the same result occurred. I was suspect of the supply valves we replaced because they wouldn't close properly. So this opening we replaced the valves again. That didn't help.

    This opening the pool was dirtier than usual due to a late closing last season and the lack of pressure for the last month of the season. So my pool guy took the filter apart again and did a very thorough cleaning with water only. We put the system back together and noticed that the pressure held for three hours or so instead of a half hour.

    Now I'm wondering a few things...

    Since we replaced 2 of the 3 supply lines already AND when we isolate the lines we experience the same loss of pressure and basket of air AND the cleaning of the fingers helped could it be we need to chemically clean the fingers? AND is the 2 hp pump too much for the system? Or is it something else?

    When we start up the system or bump it, it flows wonderfully. Then it slowly loses pressure and build air bubbles in the basket until we finally lose all pressure.

    We would greatly appreciate any thought you might have. Thank you.

    Pooless in NY



  2. Back To Top    #2
    Richard320's Avatar
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    Re: A lot has been fixed but still losing pressure...

    When we start up the system or bump it, it flows wonderfully. Then it slowly loses pressure and build air bubbles in the basket until we finally lose all pressure.
    I think there are two problems.
    1) Suction side air leak. See below.
    2) Dirty filter.

    If flow improves after bumping, the filter is doing its job. Your pool is just so dirty the filter loads up.

    The air leak is something else. Are you sure it's air and not just bubbles? After its been running a while, if you open the air bleed on top, does air hiss out first, or does water shoot out immediately? When I manually vacuum, if the head gets stuck somewhere, I see tons of bubbles in the strainer basket. But it's not air. It's cavitation from water starvation. If I open the bleeder, nothing but water flows. If you get the same thing, then I'd suspect you have a clogged or collapsed line. If air comes out, then you are drawing air, and you need to find the source.
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

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    Re: A lot has been fixed but still losing pressure...

    Thanks Richard. We're getting small bubbles that build up in basket over time. It seems that the cleaner my pool gets the less of a problem this is. When I open the bleeder air does hiss out. If air is being drawn in wouldn't closing each of the valves one at a time valves help determine if it's from one of the supplies? We not only tightened all supply connections but just replaced all of the topside pipes when we we replaced the valves last week. Any thoughts on how to trace the air leak?

    I'm also not losing water now. This was a problem with the bad lines we replaced before.


    Much appreciated.

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    Richard320's Avatar
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    Re: A lot has been fixed but still losing pressure...

    Quote Originally Posted by Elwoody View Post
    Thanks Richard. We're getting small bubbles that build up in basket over time. It seems that the cleaner my pool gets the less of a problem this is. When I open the bleeder air does hiss out. If air is being drawn in wouldn't closing each of the valves one at a time valves help determine if it's from one of the supplies? We not only tightened all supply connections but just replaced all of the topside pipes when we we replaced the valves last week. Any thoughts on how to trace the air leak?
    Not if the leak is between the valve and the pump..... like the pump strainer gasket. Several years ago someone here was hunting down a leak and ultimately it turned out to be a pipe coupling. The thing was so tight he thought he'd already glued it, but it turns out it was just friction-fit! Coat any connections with shaving cream and see if it gets drawn in. You might even see foam in the returns.
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

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    Re: A lot has been fixed but still losing pressure...

    Great idea. Will do. Thanks.

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