high flow Delta shower body rough with a 2.5 gpm shower head. Does it help?

Joseph_4

I install delta shower bodies for my customers generally.. By shower body ONLY rough (where you dont need a tub spout) they have a high flow model R10000-unbxhf. I dont understand what its purpose is. even the regular universal r10000-unbx depending on your psi 40-80 the gpm is from 4.5 to 6.8. If my shower head is 2.5 gpm what does a high flow help, I can only get 2.5 gallons out of my shower head? I am including pictures of the port out to shower on both models
Thanks for any help
Joe Hardoon
HHI Services

mikedo

most times theres a restrictor in the shower head its illegal to remove it but some people do

mattmia2

Multi head showers have higher flow rates. Probably some other commercial uses too.

STEAM DOCTOR

But 9 gpm or whatever the high flow shower body is rated for?? Can't imagine any showerhead with that flow rate. So I guess the OP's question is, what is the point of the high flow shower bodies, if the shower head will never allow anything remotely close to that flow rate. 

Tim Potter

I can attest to the high flow bodies working well even with lower flow shower heads, they are the same cost as the regular rough in bodies as I recall. If you use the "T-17-T xxxx-xx" trim kits you can throttle the water flow down without changing the temperature, then fire it up to rinse, I have done several like this over the years. all is well.

Tim

Joseph_4

Tim. The math makes no sense. if its limited to 2.5 gallons then why does it work?

hot_rod

I think those shower head flows  are rated at 80 psi
Most prvs are factory set at 45-50 psi, so you probably get less gpm then the the rating

since the distance from the valve body to the head us short , I don’t see the larger body adding much gpm?

Tim Potter

Joseph_4, I certainly cannot explain why it works or how it works, I suspect that the high flow body does not restrict the water at all, and therefore, the water saving feature depends on the low flow shower head to do the work of limiting the water. I did a his and her shower at my home, one shower had the standard flow rough in fed by half inch Pex, and the other had the high flow rough in fed with three-quarter inch Pex. Both trims were Delta T-17-T xxx-xx using the same model shower head. The three-quarter inch high flow valve body had much more pressure and flow than the half inch standard flow valve body. All I know is that I use the high flow side and I liked it. 😊

Tim