Pressure Balancing Loop

[M3]

I am installing a Moen Exact Temp shower spa with 4 body sprays and received a plumbing diagram from Moen.. I'm sure Moen does a lot of testing, but I've looked at other Pressure Balancing Loop diagrams and Moen's is different. I've attached their diagram.

Most diagrams I've seen had the supply line entering somewhere in the middle of the loop, then Tee off to left and right... I've called Moen and they say it is correct. I'm using 3/4" copper to the mixing valve and to the flow valves, then 1/2" out of the flow valves to the heads.

Any thoughts? I just don't want to install and have the pressure be off.

Thanks in advance.

 

[Krow]

Pressure will be a constant at all heads , regardless of where the supply T's in, because of the loop. I usually do my T's in the centre of the loops for aesthetic purposes only and nothing more. Just looks neater

 

[Sponsor]

 

[hj]

The benefits of a "pressure balancing" loop are vastly overstated, IF you only have a single connection. The only way a balancing loop has a benefit is if the heads are widely separated, OR, in your case, if you tee off after the volume control valve and make a second connection to the riser on the left side. (And in that case the upper and lower horizontal runs are redundant.)