Grohe Grohsafe Pressure Balance Valve

[ccwenk]

I just got done installing this valve in a new shower I built. Based on what I was told (and sold) at the plumbing supply, I installed a diverter for a hand shower on the output of this valve. Now (too late), I am reading the instructions and it says not to install a shut-off on the output leg of the valve. I am worried that I have effectively done that if I use a hand shower with an on/off function.

What is the reason for not having a shut-off on the output of the valve?

Thanks for your help.

[hj]

Not sure about this valve, but usual reason is that you might tend to use THAT on/off valve instead of the one in the valve, thus subjecting portions of the valve to unusual pressures, and possibly creating back flow or crossover problems in the piping system.

[ccwenk]

Thanks for the fast reply. That makes sense to me. I guess that I will need to make sure that the water is always shut off at the main valve after the shower is used.

Any other ideas or advice??