Center Drain Valve - Hose Hook-Up?!


New member
Aug 5, 2019
I am trying to figure out what goes where......first time center drain owner

I installed the pump and filter and need to figure out the connections for the water lines......the valve for the center drain has me baffled

Any help as to what runs where:
Outlet back to pool
Center drain valve (2 ports)



Gold Supporter
Jun 18, 2014
Glassboro, NJ
My best guess is a mixing valve. Looks like the red tag says SKIM.

You can control flow thru each by turning the valve.

how about another pic looking a valve face.


Well-known member
May 6, 2018
The side connection goes to the pump. The top goes to the skimmer.

If this valve is like the 4 port Hayward valve I have you need to turn the pump off before changing it as it can totally shut the supply to the pump off.


New member
Sep 14, 2017
Chicago, IL
The top valve (red, port 1) is connected to your skimmer. The side valve (blue, port 2) is already connected to your center drain under the pool...that valve will then be connected to your pump, then to the filter and ultimately to the pool return. I generally keep the center drain valve in the 12 o'clock position as this gives me a 50/50 mix of water being pulled from the skimmer and also the center drain. This works great because it allows for the skimmer to do its thing and keep the leaves and such out, but also allows the center drain to the keep the water circulating from the bottom of the pool.

When it comes time to vacuum, I turn the center drain valve to the full port 1 (red) position to allow for maximum suction from the skimmer which is what feeds the vacuum.

I use the center drain port on full port 2 (blue) if I'm in the pool using a brush for a routine cleaning of the bottom of the pool. This allows me to just brush the dust or fine debris towards the center drain and onto the filter. I've been known to use the center drain on full blue also if I'm trying to heat up the pool a little quicker on sunny days because it allows for the colder water on the lower levels of the pool to be circulated to the's a thing of beauty. I'll also go heavily towards the center drain value if there's a lot of activity in the pool because once everyone gets to splashing and stirring things up, the center drain really shines in helping to remove the fine particles from the pool. I try to avoid having it solely on the full port 2 on a regular basis if people are swimming because this does place all of the suction to that one port on the bottom of the pool. The covers for the center drains are designed to avoid someone being held down by suction by why temp fate...its just as easy to keep it mixed between the two.

Hope that helps...


Well-known member
Sep 18, 2012
IL, NW of Chicago
Apparently some above ground pools in freezing climates have floor drains? For some reason I thought that wound't work well. How do you purge it from freezing in winter? I would have liked a floor drain, but didn't know to investigate one when my pool was being installed. This is my 1st pool, and I didn't know this place existed at the time


New member
Sep 14, 2017
Chicago, IL
Yep...Im in Illinois as well and my floor drain survived the polar vortex last year like a champ. It's necessary to blow out as much of the water possible out of the center drain and then slam shut the main drain valve to create an air lock in the piping under the pool. I also like to add a couple gallons of the non-toxic pool antifreeze to the line for takes a bit longer, but I figure a couple bucks for 2 gallons of the stuff is pretty cheap insurance to avoid having to remove the liner and replace the piping and valve if it were to rupture.

If I remember correctly, most people advise to use an air pump that has low pressure but a high volume of air to blow out the lines in order to avoid putting too much strain on the pipe connections. I've seen quite a few people recommend the Cyclone Vacuum and Blower (google them...easy to find)...I'd love to have one but cant convince myself to drop $300 on one just yet. I use a pvc connection that attaches to the main drain valve and has a schrader valve (bike tire valve) on it. I connect that to my air compressor and blow out the line several times until I'm satisfied it's as clear as I'm going to get it. I'm still refining my process on this, but it's worked pretty well so far over the past couple years. I'd suggest checking youtube for videos on winterizing an above ground main'll have to sift through the good and bad, but it's a good place to start.