Thread: Pipe sizing for Sloan-valve toilets

I have a client who is having an old (1920's) large house re-plumbed. She was aware that all the old tank-less Sloan valves were fed with 1 1/4 inch pipe. (Her service line is 2-inch lead.)The plumber is redoing these runs with 3/4 or 1 inch pipe. I've been trying to find a solid source of info for this, and coming up empty. Does anybody out there know how much water it really takes to feed one of these things? Will that 3/4 inch line be able to handle the job, assuming a normal 50 PSI municipal supply?

I have no experience with this, and Sloan's website is not much help. Here is one link that may be useful:

Install Commerical Toilet in Residence | Terry Love Plumbing & Remodel DIY & Professional Forum

Go to a commercial supply house . they can give you the specs you are looking for.