What's the purpose of this pressure side pipe (one without a ball valve) and opening?

[baip]

You can see that the right-most pipe is split from the return but does not have a ball valve -- what's the purpose of this line? I don't have any water features or pressure-side pool cleaner (I think). I'm also not sure about the opening below. It has a screwed-on cap but when I unscrewed it, there was not water pressure.

IMG_20190927_172031.jpg

• baip
• Sep 27, 2019

 

[proavia]

The right most pipe is probably for the returns to your pool.

The ones circled in red are on the suction side.

That round plug in the later pics is to allow air into the return line near your steps to simulate a return jet with bubbles.

Without you telling us more about your pool, it will be difficult to tell you more about the valves in your pics. Fill out your signature with your pool, pool equipment specs (including model numhers) and what testkit you are using.

 

[JamesW]

One of the return lines goes to the returns and one goes to the step jets.

The caps go to the step jet venturi air inlet.

If the return valve is closed, do the step jets get stronger?

 

[baip]

The right most pipe is probably for the returns to your pool.

The ones circled in red are on the suction side.

That round plug in the later pics is to allow air into the return line near your steps to simulate a return jet with bubbles.

Without you telling us more about your pool, it will be difficult to tell you more about the valves in your pics. Fill out your signature with your pool, pool equipment specs (including model numhers) and what testkit you are using.

Thanks. Sorry about the confusion with the red circles on the suction pipes -- I reused an old picture. I thought the second pipe from the right (the one with a ball valve) controls the returns to the pool (which I shut off during winter), but I can do a cautious testing.

Not sure why my signature didn't show up correctly; I can see it fine. Here it is:
> 25K gal, IG vinyl, 2 skimmers, 1 main drain, 3 returns, 1 HP Hayward Super Pump, 250 lbs Hayward sand filter, Hayward chlorine feeder, K-2006 Test Kit

 

[baip]

One of the return lines goes to the returns and one goes to the step jets.

The caps go to the step jet venturi air inlet.

If the return valve is closed, do the step jets get stronger?

Ah, I see. I'll test tomorrow.

 

[baip]

It turns out that the valve controls the two normal returns and the spa jet is always on.