3 way valve (diverter) flow question

[Tiger275]

Do the different valves have a "meaningful" flow difference when considering a 1.5"x 2" vs. a 2"x2.5". Obviously the pipe size will impact the answer but I am just asking about the valve body itself.

For example...if you have this scenario... 2" input -> valve -> 2" out & 1.5" out

Would there be a flow impact of choosing to use a 2x2.5 so that the 2" pipes are inside and a then use a stepdown for the 1.5"
OR
Just keep it simple and use the 2x1.5 so you have the 2 "coupled and the 1.5 inside

Is it much ado about nothing or given the option, does it make a difference?

 

[mknauss]

At typical flow rates from pool pumps, there is no difference. Keep it simple.

 

[cfherrman]

One fitting being smaller such as a valve is not much

50' of 2" compared to 50' of 1 1/2 and you have something

 

[Tiger275]

Thanks for the input. Just trying to accumulate the parts for the pad remodel and trying to move everything to 2" on the pad as much as possible. But this one wasn't really clear. Since I am trying to avoid touching the plumbing aware from the pad at this time.

 

[cfherrman]

Lots of valves will take a 2" inside and 2.5" outside or similar, very good for future repluming

 

[Tiger275]

Lots of valves will take a 2" inside and 2.5" outside or similar, very good for future repluming

Yep...that was my question. Any value in going this route over a 1.5x2? Seems like it would be helpful from a future proofing perspective, but would not have a truly significant impact (compared to some other choke points).

 

[Tiger275]

2 related questions.

1) I see lots of talk about unions for equipment. What about unions on valves? Worth it? Anyone have a good pic of how this would work when using a 3 way valve?
2) when 'plumbing for the future' for adding a heater/heatpump, is there a way to install a 3-way so that the long part of the T is in the main run and the short part is the "future stub"? So that when you are not using the heater, the flow is straight. It seems like the three way doesn't really want to seal off the short t side.. especially when under pressure but with no closed end to create back pressure..

effectively so that it looked like this...


or is it better to use standard pvc t and then 2 way valve in the future.. like this...

 

[mknauss]

As long as you use Jandy valves, they are fully repairable. So really no need to plan for replacing the valve body.

 

[Tiger275]

As long as you use Jandy valves, they are fully repairable. So really no need to plan for replacing the valve body.

Not sure I follow. Sorry.

My current setup has a valve that must be replaced because there is not sufficient pipe to connect new stuff. So when I swap it out, I plan to also replumb the pad and straighten some really twisted plumbing.. Just want to add in the plan for the future heater at the same time.

 

[mknauss]

Not sure I follow. Sorry.

Your first question was about unions for valves. Not necessary if you use Jandy.

As far as the future heater set up, if you want a heater bypass, you would need a three way at the inlet and just a T at the outlet, with a check valve between the T and the heater.

 

[Tiger275]

Your first question was about unions for valves. Not necessary if you use Jandy.

As far as the future heater set up, if you want a heater bypass, you would need a three way at the inlet and just a T at the outlet, with a check valve between the T and the heater.

Thanks. I get it now on the Jandy's. Essentially just redundant to put the unions because everything is rebuildable.