bubbles coming from bottom drains

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waterboy
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bubbles coming from bottom drains

Postby waterboy » Sat 13 Jul, 2019 10:30

I have bubbles coming from the bottom drain inlets when the pump is running and the line is partially valved off. The pool is 8'deep. The more I open the valve the more air I get to the pump, however when the pump is off no bubbles come out. The only thing that makes any sense would be a crack in the drain line but why would it stop with the pump? I do not seem to be loosing any water. Any ideas?


Teapot
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My Pool: 12 x 24 (45m3) liner pool, Triton TR60 filter with AFM glass media (Activate) and variable speed pump running 0.08HP
Location: UK

Re: bubbles coming from bottom drains

Postby Teapot » Sun 14 Jul, 2019 00:46

Water is larger than air molecules and easier to move but it does sound like an air leak. That valve sounds suspicious to me, are the O rings in good order, not hard and flat with age?
waterboy
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Posts: 6
Joined: Sat 13 Jul, 2019 09:48
My Pool: 25000 gal concrete, 1.5 hp pump w/.75 cleaner pump de filter

Re: bubbles coming from bottom drains

Postby waterboy » Sun 14 Jul, 2019 10:48

the valve that I referenced is a pvc ball valve for balancing the flow between the bottom and the skimmers just before the pump and is 8' above the bottom of the pool. I don't see how air can travel down through that much water against the flow of the water.
Teapot
Pool Industry Leader
Pool Industry Leader
Posts: 1337
Joined: Tue 17 Oct, 2017 10:52
My Pool: 12 x 24 (45m3) liner pool, Triton TR60 filter with AFM glass media (Activate) and variable speed pump running 0.08HP
Location: UK

Re: bubbles coming from bottom drains

Postby Teapot » Sun 14 Jul, 2019 13:32

Yes I guessed which valve, I am working blind here so please forgive. Is there a hydrostatic valve in the bottom of the main drain?

Also there is no point in trying to balance the flow between skimmer and main drain. Main drains do next to nothing but circulate clean water and reduce the skimmers action. All dirt enters from the surface and that is the best place to remove it.
waterboy
I'm new here
I'm new here
Posts: 6
Joined: Sat 13 Jul, 2019 09:48
My Pool: 25000 gal concrete, 1.5 hp pump w/.75 cleaner pump de filter

Re: bubbles coming from bottom drains

Postby waterboy » Sun 14 Jul, 2019 13:36

Not sure, what is a hydrostatic valve?
Teapot
Pool Industry Leader
Pool Industry Leader
Posts: 1337
Joined: Tue 17 Oct, 2017 10:52
My Pool: 12 x 24 (45m3) liner pool, Triton TR60 filter with AFM glass media (Activate) and variable speed pump running 0.08HP
Location: UK

Re: bubbles coming from bottom drains

Postby Teapot » Sun 14 Jul, 2019 14:27

It's a valve in the bottom of a main drain that opens if there is water under the pool shell rather than possibly floating the pool. They sometimes develop little leaks. Just trying to eliminate possibilities.
waterboy
I'm new here
I'm new here
Posts: 6
Joined: Sat 13 Jul, 2019 09:48
My Pool: 25000 gal concrete, 1.5 hp pump w/.75 cleaner pump de filter

Re: bubbles coming from bottom drains

Postby waterboy » Sun 14 Jul, 2019 15:21

just looked it up and I believe you have the answer. Thanks Teapot
Teapot
Pool Industry Leader
Pool Industry Leader
Posts: 1337
Joined: Tue 17 Oct, 2017 10:52
My Pool: 12 x 24 (45m3) liner pool, Triton TR60 filter with AFM glass media (Activate) and variable speed pump running 0.08HP
Location: UK

Re: bubbles coming from bottom drains

Postby Teapot » Sun 14 Jul, 2019 16:33

Please let us know and watch this video on main drains and the enormous flow and you'll see main drains do very little, you actually have to push dirt into them.

https://youtu.be/0IOUGhuKkSM

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