Bath pressure problem

freemarmoset · Jul 29, 2006

Hi,

I've got my new plumbing in, and have a problem with the tub/shower pressure.
It's fed by 1/2" copper coming off the same 3/4" pipe that runs to the toilet and sink. I'm getting about 6 gallons per minute flow from those fixtures, but less than 2.5 gpm from the tub filler.
At this point I'm thinking that the shower valve is faulty (brand new American Standard one-handle), and I should cut it out and clean it or replace it. Before I start cutting, does this sound right to you all?

Thanks,
Joe

Jimbo · Jul 29, 2006

At this point, hold off on "cutting it out". The operating cartridge can be removed to check for any debris which may have gotten inside.

You did mention it is brand new, and there is a "top" and "bottom" to a shower valve. The outlet to the shower often has a restrictor in it. The "bottom" outlet to the tub filler would have no restriction. If the valve was put in upside down, then you have a problem!

Sponsor · 2022-01-29T12:20:58-0800

freemarmoset · Jul 29, 2006

Still confused

Ok. So I removed the pressure balancing valve and tested again. Got about a 7gal/min flow rate. I reassembled and it went back down to about 2.5gal/min. I guess I would expect some reduction from the balancer, but should it be that much? Could that part be faulty?

freemarmoset · Jul 29, 2006

BTW, I did double check and it isn't installed upsidedown, so that's not the problem either.

freemarmoset · Aug 25, 2006

Flow rate still an issue

Thought I'd reply to this one more time to see if anyone had any further ideas.
I'm stumped. 40psi inlet pressure. Between 6 and 7 gal/min flow rate w/o pressure balancer. 2-2.5 gal/min with pressure balancer. I even returned the pressure balancing valve and put in a new one. No change.

I really wish I could figure this out. Please let me know if anyone has any ideas.

Thanks,
Joe

Jadnashua · Aug 25, 2006

Do you have both supplies turned on? I've read that if both supplies aren't turned on, it can push the pressure balance valve to one limit and restrict the flow.

freemarmoset · Aug 25, 2006

Yes. They are both fully on.

When I do shut off one of the supplies it does do just that--reduces it to even more of a trickle.

Mikey · Aug 26, 2006

What about the spout?

Sounds like the one thing in common is the spout. Is there a giant piece of crud plugging it up, or is there a diverter in the spout that is partially closed?

Verdeboy · Aug 26, 2006

I did some research and found that, at 80psi, standard showerheads work at 2.5 gpm, while watersavers work at 2.0 gpm. Your inlet pressure is 40psi. So, maybe your water pressure isn't that great, period. See if all your valves are open all the way, starting at the curb box.

Bath pressure problem

Users who are viewing this thread

freemarmoset

New Member

Jimbo

Plumber

Sponsor

Paid Advertisement

freemarmoset

New Member

freemarmoset

New Member

freemarmoset

New Member

Jadnashua

Retired Defense Industry Engineer xxx

freemarmoset

New Member

Mikey

Aspiring Old Fart, EE, computer & networking geek

Verdeboy

In the Trades

Similar threads