Is piping sufficient?

[Alternety]

I just moved into a new house. I took my first shower last night (to the relief of the neighborhood).

The shower performance was pitiful. There are three positions. One just puts out water that just runs out and down. Massage makes a useless little spitting stream. The last is the only one that works. It is adequate to take a shower but has no force at all. The water comes out and starts curving down rather than maintaining enough velocity to continue straight.

The house is plumbed with two water manifolds fed by a 3/4" pex pipe. The pipes from the manifolds to the individual points of use are 1/2" pex.

Pressure from water system is set to 40/60.

The question. Is this piping sufficient?

 

[Terry]

You may want to change the shower head, or at least remove it and see how much water you are getting.

With the right head, you only need about 2.5 gallons a minute.
Some heads require quite a bit more than that.
Then there are those that work like a "rain head" those are very soft.
I would think that 1/2" pex to the shower valve would be fine.
That's not to say that there isn't something blocking the cartridge openings though in the faucet.

 

[Sponsor]

 

[Leejosepho]

I just moved into a new house ...

Does that mean "new to you", or actually new?

The shower performance was pitiful ...

Pressure from water system is set to 40/60.

The question. Is this piping sufficient?

I would guess it is, and that you either have a pressure problem or some kind of flow restriction(s).

Check the pressure guage with a couple of fixtures running open (both hot and cold together) to see how much fluctuation or constant pressure you have at the guage. If the pressure there seems sufficient and steady, I would next begin checking/isolating various lines and faucets for obstruction(s).

 

[Alternety]

It is new new.

I realize there is a flow limiter somewhere in the fixture. But this is silly. I have had a lot of showers with said restrictors, but they worked in all modes they were designed for.


I have not seen any pressure anomolies while running water.

 

[Terry]

Most faucets are rated at 5 to 7 gallons.
The shower head is where they restrict them.

 

[Verdeboy]

Could be as simple as the shut-off valves not open all the way or a plugged shower head.

 

[Alternety]

It may also be the pipe, but I am going to take the head apart. With the tub runing I get over 4 gpm (not what Terry suggests). With the shower on I get just a tad over 1 gpm.

It just seemed to me that a head designed for low flow ought to at least function. It appears they intend for you to remove the restrictor.

 

[Terry]

You don't mention what brand faucet you have, so as plumbers, we are just guessing at your problem with your new home.

Here is a quote from the Moen site
Posi-Temp offers a flow rate of 6.3 gallons per minute (GPM) at 60 psi

That would be assuming no friction loss based on length of tubing and 60 PSI
1/2" tubing is normally good for two plumbing fixtures.
https://terrylove.com/watersize.htm

Low water pressure Delta site

 

[Alternety]

Terry - the link to your page on pipe size was very useful. You might want to add pex to the yellowed in area. I have pex.

I meant to provide the brand and model on my initial post. Sorry about that. I went and got the documentation and found some useful stuff.

Hansgrohe thermoBalance II control

Recommended pressure 45-72
Nominal capacity at 45 psi 8 gpm
Nominal capacity at 60 psi 11.5 gpm
Max flow rate of shower head 2.5 gpm

I have to find the docs for the shower head itself.

 

[Terry]

I've seen some tub showers that were plumbed with 3/8" pex that worked pretty well.
Most restrictions are in the valve itself, and of course the shower head.

 

[Alternety]

I am rather hpoing this gets better. I have 3 more of the same heads to install.