Waterfall pump replacing with vs pump

[fromm]

Hello,

My pool has two waterfalls on two pumps that are separate from the main filter pump. Each waterfall is on a dedicated 1.5hp single speed pump. Each pump is fed by two suction ports (why are there two? Is one a backup? I assume they are plumbed together underground before the pump.)

We never use one of the waterfalls because the fall is several feet and the sound is far too loud for 'ambience'. I have a spare vsp pump that I want to connect to the waterfalls. I want to plumb both waterfalls to the vsp pump with a Jandy valve to each waterfall on the supply side of the pump. The idea is with the pump at high speed and the Jandy valves wide open, each waterfall will flow at max. If I want one waterfall to have less or none, the valve can be closed.

My question is, should I plumb the suction side from the old pumps together into one for the vsp pump or only use one of the suction lines and cap the other one? Thanks in advance for any input.

 

[cowboycasey]

Welcome to TFP

There are 2 so no one can get trapped, its the law so no one can get stuck under water... You can connect the 2 together ( recommended ) or cap 1 off ( but it may turn into a green monster and you will never be able to get the algae out of it) into your VSP pump and out of your pump into a 3 way Jandy valve so you can select how much water goes to each waterfall and coupled with your VSP you can select how much and how fast the water comes out... Sounds like a much better option and it saves money in the long run

Stick around and check out the site

 

[HermanTX]

I support @cowboycasey comments that it is best to connect the 2 suction lines together to avoid having 1 line stagnant.
Also each suction lines require 2 ports in the pool which is why you have 4 showing in your picture. This reduces the suction force for each to avoid entrapment.

 

[fromm]

Got it. I didn't think about the unused line going stagnant. Thanks for the replies!

 

[fromm]

Hello Everyone,

One more question. Referring to the image in my original post, the suction lines from the pool are 2-1/2". The 90s reduce to 2" before the existing pumps.

The question, is it better to keep it 2-1/2" all the way to the pump or is it okay to keep the 2" from the existing 90s? I wanted to keep it 2-1/2" all the way but I didn't realize that 2-1/2" sch 40 is not something regularly supplied. I would have to put off this project for another weekend.

 

[Rich D]

The 2.5" line from pool is sized that big to reduce pipe friction in the long run. It changes to 2" because that is the intake size on the pump. I do not think you will have any significant friction by using all 2" from those reducers.

 

[kadavis]

Use a 2.5" x 2" 3-way Jandy Valve,Jandy | Never Lube Valves