What is the second hole in skimmer for?

[Thinkly]

I am borrowing this pic from another thread, but my skimmer looks the same. When we closed last week i just plugged the "back" hole, the one with the gizmo in it in this pic. In my skimmer, the back hole is the only one that blew air. It is also the hole that i attach my vaccum to and from what i can tell, the only hole that even functions.

What is the other one for? I think mine isn't even open if i recall, in other words i think i can see plastic in the bottom of the hole if i recall.

 

[duraleigh]

It can be used for several purposes. Most commonly, to connect more than one skimmer in "series" or to connect a main drain to a skimmer. Or, like yours, it can remain plugged and is unused.

 

[waste]

Psst... Dave don't forget it being used as a reserve line (I think I did this so no one else would see it ) :lol:

Thinkly, if the other hole had a plug in it already, don't mess with that plug :!: Do you have any reason to suspect that it might do one of the things Dave or I said?

 

[Thinkly]

I'm not sure what reserve line means, but I only have one skimmer and my main drains and skimmer come to the pad via different lines. Also the hole i speak of doesn't have a visible "plug" in it. It is recessed, just like the other hole, but if memory serves me correctly, there is plastic covering the hole down a few inches.

 

[waste]

The second port seems to be unused, so they probably plugged it from the bottom

The reserve line is just a backup line that is connected to the pool on installation but the poolside ports are plugged and the pipes aren't connected to the filter system (until needed) If the main skimmer line broke or developed a fatal blockage, the reserve line could be opened and plumbed in without the need to dig a lot or break up sections of the deck.

 

[WestSidePool]

I was looking at mine when i was closing my pool, and they capped it off from under the skimmer with a PVC cap.
When i looked more closely at it, it said 2" on the closed hole, and the open hole (which is being used) said 1-1/2".

So i'd say its so the installer could run either 1-1/2 or 2" piping to it.