Skimmer and Main Drain

lckjsharp

Member
Mar 14, 2022
8
Seattle. WA
I was wondering if the main drain is supposed to be attached to the skimmer or can each be isolated and ran back to the pump on their own with their own control valve. I live in a cold climate where it freezes so I was thinking it would be best to have an isolated main drain as well as the skimmer isolated for winterizing purposes. I have seen most pool builders attach the main drain from the pool to the skimmer, but what it best especially in cold climates. Any thoughts?
 

Texas Splash

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I was wondering if the main drain is supposed to be attached to the skimmer or can each be isolated and ran back to the pump on their own with their own control valve.
While it can be done either way (sometimes a builder's option), it's ideal to have the drain plumbed separately to the equipment pad if possible.
 
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Jimrahbe

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Ick,

Most all old pools had their main drains plumbed into the bottom of the skimmer.

Most new pools have their main drains plumbed back to the equipment pad. (At least in my area)

Thanks,

Jim R.
 

Texas Splash

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Is that common to build pools without a main drain?
I don't know if I'd say common, but certainly not a limiting factor to not have one. Proper water circulation and surface skimming are most important, and a poolside skimmer(s) will support that just fine.
 
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proavia

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You should consider having two skimmers - each plumbed separately back to the equipment pad. Usually, these are placed at opposite sides/ends of the pool based on prevailing winds. Main drains are optional - but can be beneficial for some pools.
 
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pjt

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I never realized you could build a pool without a main drain.
Neither did I until I did some research. I built my current pool without a main drain and I'm very happy with that decision.

I just thought it was standard because of sanitary purposes.
For a typical pool, a main drain does little for circulation and distribution of chlorine.
 
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lckjsharp

Member
Mar 14, 2022
8
Seattle. WA
I,

Curious why you think an equalizer line would be required?

Thanks,

Jim R.
I saw a video where a guy talked about it having an equalizer on a skimmer. Here is the link
and its about 2min in where he mentions it. I just figured it was for safety reasons to have an equalizer. I wasn't sure since there are two ports at the bottom of the skimmer. So, since I will run the one line back to the pump...do I just cap off the other? I have a Pentair Bermuda Gunite Skimmer 2" slip.
 

Jimrahbe

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I,

An equalizer line is used so that if the water level falls below the skimmer's mouth, the water will come in from the equalizer line. But.. only if you have a floating diverter installed under the skimmer basket. You can add an equalizer line, if you want, but I see no reason to add them.

The video gave the impression that they were needed, but I can't see why??

Most pools down here do not have equalizer lines. The skimmer line closest to the water is capped, and the other line is plumbed back to the equipment pad as the skimmer input to the pump.

If you have two skimmers (which I always suggest) then both skimmers are independently plumbed back to the equipment pad.

Thanks,

Jim R.
 
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mas985

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Equalizers can be useful for pools that experience a lot of leaf drop and where the skimmers can get easily clogged. If you don't get much large debris in the pool, they aren't really needed.
 

Jimrahbe

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My pool builder automatically installed equalizers below both of my skimmers. What he did not do is provide the floating diverter that turns them on.

Without the floating diverter I don't see any way they can work. I don't get a lot of leaves, so not at all worried about it.

Thanks,

Jim R.
 

mas985

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Does the equalizer have an equalizer valve on the line? The float helps prevent the skimmer from draining but it is really the equalizer valve that opens when there is blockage in the skimmer.

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vtpools

In The Industry
Apr 26, 2019
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VT
Without the floating diverter I don't see any way they can work
Just to add a little bit to this discussion, without the float valve an equalizer line will work, sort of. Water seeks its own level, so as soon as the water drops below the mouth of the skimmer water will get pushed up into the skimmer through the equalizer line and fill the skimmer, at which point the water will get sucked towards the pump. Likewise if a bunch of leaves are sucked into the skimmer and the basket gets blocked, water will follow the path of least resistance and get pulled up through the equalizer line.

At the risk of starting a heated debate, the only other thing I'll say is that equalizers shouldn't be installed and the main drain should be run all the way back to the pump and not into the bottom of the skimmer.
 

Jimrahbe

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vt,

You bring up some very good points and may be correct. I'll have to look at my set up once it gets a little warmer.

Not sure I want to drain below the skimmers, just to find out though... :mrgreen:

Jim R.
 

proavia

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vt,

You bring up some very good points and may be correct. I'll have to look at my set up once it gets a little warmer.

Not sure I want to drain below the skimmers, just to find out though... :mrgreen:

Jim R.

Maybe block the skimmer throat or hold the weir door closed to allow the water level in the skimmer to drop.
 

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