Shower head dripping when tub is filling up

[Terry]

Hello,

I just joined the forum because I need help with a new tub/shower valve I just installed. This is a new installation and I have easy access to all the piping. It is a Delta 13/14 multi-choice valve.

The issue is when I turn on the valve plenty of water comes out if the tub spout (actually it's just the 1/2" stub out and no spout yet), but the water trickles out of the shower the whole time.

After researching everything I can the only possible cause I can find is that the tub spout is about 27" below the valve (the shower head is about the same height above the valve). The problem is that the manual says the tub spout should be a minimum of 8" below the valve and a maximum of 18" below. I wonder if the extra 10" of pipe is causing a restriction that is forcing water up and out of the shower head.

I guess the only other information I can give is the setup:
The main line is 1" line from the well to the house at about 60psi and the flow from outside can peg my flow gauge. 1" runs to 3/4" to the bathroom with 1/2" going up to the valve. 1/2" also runs to the tub spout and shower head.

If the problem is the extra length of pipe I wonder if I can replace the middle section of pipe between the valve and the tub spout with 1" to reduce the drag/restriction.

,Terry

 

[johnjh2o]

It sounds like you have the valve body in upside down. If you can see the valve body there is a directional arrow on it. The other possibility is that you used PEX or CPVC pipe between the valve body and the spout. PEX and CPVC have a smaller ID then copper causing some water to backup into the shower head.

John

 

[Terry]

I did use CPVC I don't have any copper in my home due to cost and installation.


Can I just increase the majority of the pipe to 1" CPVC or something? Or maybe replace the drop with 3/4" CPVC. I guess if I had to I could make just the tub spout in run in copper but I have never used copper and would have to figure out how to do the joints.

 

[johnjh2o]

Sorry to say but copper is what is needed. It would be just three joints. It's not that hard to do.

http://www.thomaspenrose.com/diy_plumbing_01.htm

John

 

[LiQuId]

going outside of the manufacturers recomedations for installation is also not a very good idea, changing to copper would definatelly be better and offer less restriction but if your manual says "maximum 18 " for the tub spout " then there is a possability that pipe wall friction would still cause the sputtering shower Copper or not.

Water will take the path of least resistance.

 

[Terry]

I custom built my entire home and this shower uses some very expensive stone and has already been grouted and sealed. If I can find a way around it then I am going to keep the setup and figure a way to change the piping to work.

I am going to try and increase the pipe of the spout and if that improves things, but it needs a little more than I could always create a little more resistance on the shower head side.

 

[johnjh2o]

Can you access the valve from behind the shower? You had mentioned increasing the spout size to 3/4" how were you going to do that? It sounds like you will have a great home when done why would you screw up a shower just for the price of some tile work?
Keep in mind this is something your going to have to live with for as long as your in the home. I know it would drive me nuts every time I used it. Just my opinion.

John