A picture of my pool plumbing from this past year...
1-Skimmer, 1.5" piping
1-Deep end wall about 3' deep, 1.5" piping
These combine in a 3-way valve, into another 1.5" pipe before entering the suction side of the pump.
The suction and discharge of the pump are 2.5" ports, both with reducers to fit the 1.5" piping.
From the discharge of the pump, through 1.5" piping to the cartridge filter.
The cartridge filter has 2" inlet/outlet ports with reducers to 1.5" for the 1.5" piping.
Leaving the filter the 1.5" piping splits off at a 3-way, where it return to the pool through 2-1.5" lines.
(note-a chlorine feeder will be added after the filter this summer for when I will be out of town)
Now, I have read several threads already with no definitive answers, on whether or not I would benefit from larger diameter piping around my components. If I could go from the suction side 3-way and have those 2-1.5" lines meet into a 2" line, and run 2" all the way through until it splits off on the supply side, would there be any benefit? I currently have had no problems with the pool running with the current set-up, but am always open for suggestions. I already plan on re-plumbing the current piping as it is a mess and I could easily make shorter runs.
One thing I'm concerned about is with the flow. Kind of how choking down a pipe in the middle of it is called bottle-necking...would having a section with larger piping cause any kind of turbulence in the system and negatively impact the flow.
Any help you can provide is awesome. Obviously I won't be changing any piping that runs underground.