2" piping with Pentair SuperFlo VST (342002)

[ek1]

I am in a middle of replacing all the piping and most of the equipment in my aboveground pool. I decided to go with 2" piping everywhere. I am using a Pentair SuperFlo VST pump (342002). After taking the pump out of the box, I realized that the pump comes with unions for 1.5" pipe (Pentair part 350093) (this is according to my plumber):





Can someone recommend a union designed for a 2" pipe? I would rather not use reducers, etc. - this defeats the point of using the 2" pipe.

 

[ajw22]

I would rather not use reducers, etc. - this defeats the point of using the 2" pipe.

The input to the pump is 1.5" so it will be reduced at the pump or a few inches before if you use a reducer. You cannot change that.

Just use a reducer.

 

[ek1]

The input to the pump is 1.5" so it will be reduced at the pump or a few inches before if you use a reducer. You cannot change that.

Just use a reducer.

Ok....I have a _really_ dumb question, please bear with me. When people talk about 1.5" piping vs. 2" piping....are they referring to the inner or the outer diameter of the pipe? I am asking because I have a bunch of 2" PVC piping (at least according to my plumber) sitting next to my pool and it's external diameter is EXACTLY the same as the external diameter of the union that comes with my pump. Furthermore, I just tried to fit a 2" coupling (it actually says 2" on it) and it fits over the union that came with the pump. Yet, none of the diameters of any of the pieces are actually 2". What am I missing here?

 

[ajw22]

ASTM D1785 and ASTM F441 - PVC and CPVC Pipes Schedule 40 & 80

Standard dimensions and weight of PVC - Polyvinyl Chloride - and CPVC - Chlorinated Polyvinyl Chloride.

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