Plumbing Question- shower valve.

[steve terplak]

Put in a new tub for a friend (?helped? her husband).

Plumber with pex- used copper to the tub spout- as you are supposed to.

They missed getting a copper elbow for the tub spout from the list of supplies I asked them to get.

Me, trying to save time to get home for dinner and skip a hardware store run, wasn?t thinking 100% correct, and grabbed a ?sharkbite? (push fit) elbow out of my tool box. Problem solved.

Wife texted me- when filling tub, shower head dripped. I thought for a minute and realized that by using the sharkbite I was reducing the diameter to flow to the tub spout which was causing the backup to the shower head. In effect the same problem that would be caused by using pex to the spout.

I went back yesterday and could access the pipes from the backside and removed the sharkbite, sweated in an elbow. Problem solved.

Wife and husband happy. Texted last night to make sure all was good. Said it was. Said that the pressure to the shower head seemed better than before too (bonus).

So here is my question- I don?t know enough about the internals of a shower/tub valve. Would the removal of this restriction improve shower head flow too? I figure the diverter just closes off the spout which brings water to the head.

It shouldn?t matter what diameter the tub spout pipe is to bring water to the head...should it?

Just curious.
Thanks in advance.
 

[steve terplak]

Third line should read ?plumbed? with pex. Not Plumber with pex.
 

[Russ from MN]

I have used some Sharkbite fittings in the past with no problems, seem to have good flow through them.
 

[DoubleO7]

Once the diverter is pulled on the spout, water packs the pipe to the spout, right?
And thus the water bypasses that filled pipe and flows up to the shower head.
New valve or new shower head, or they were out of that shower so long, they forgot how much it flowed before.
 

[steve terplak]

That is how I assumed it worked too. Just the perceived
increase in pressure had me wondering if I was wrong.

They were never out of a shower.

But I am thinking that they just never thought that much about
water pressure.
 

[kcm.MN]

It's normal for shower heads to clog, even using city water. So even if you re-used the same shower head, it's possible they are getting more water volume due to less restrictive clogs in the head.

If any components going up the riser pipe to shower head are more restrictive (including smaller ID pipe/fittings), they would see an increase in pressure. Think of sticking your thumb over a garden hose.
 

[kcm.MN]

...And of course, there's always the possibility they're just very grateful for your help!

I've done things for people that didn't result in anything better than what they had prior, but they would swear up and down it was better. So, might also be this.
 

[steve terplak]

Lol. She was just happy to have it done.

Of course I made more work for myself. Was looking at their
house and noticed what a cluster their supply lines and valves
are.

Corrosion, non-working boiler and ball valves. Capped off
lines to nowhere.

I commented on what a mess it was and they said they were
thinking about having it all re-plumbed before too long. One
estimate was $3K.

So then stupid me said that the husband and I could do it
some fall weekend. Figure we could do it for $400 in parts.

She is a good friend of my wife. One floor, wide open
basement with unfinished ceilings. 1 bathroom. Waste pipes
recently updated. Should be easy. But I always open my
mouth and make more work for myself. No wonder I never
get my own stuff done.
 

[Steve@Advance]

"I figure the diverter just closes off the spout which brings water to the head."

Yes, that is correct. Once the diverter is closed, the spout is out of the equation.

A couple of possibilities, the old valve was clogged internally with calcium, rust, or whatever came through the pipe and didn't make it through the valve.

Or the new valve was designed with larger ports and was able to flow more volume.

Typically, the flow restrictor is in the shower head itself. They are restricted for water conservation regulations. Of course no one would ever do it, but the restrictor is usually easy to remove or modify.
 

[Mule Meat]

The Shark Bite should not have had an effect on pressure or volume.

I use them all of the time on tub/shower fixtures. What may have happend was a piece of crud dislodged while the water was turned off and got flushed into valve or stem. Then when you pulled the Shark Bite off it back flushed itself loose.

I have a line cap and a rubber hose made up that screws onto the tub and shower line. Once connected I open the valve wide open on cold then hot for a few seconds before installing the tub spout/diverter and shower head. It flushes all of the debris out. Same with a kitchen or bath facuet. Remove the airater and flush the lines. You would be surpised at how much gunk can come out of one.
 

[showcrop]

Steve, the Shark Bite will reduce pressure, BUT you would need extremely sensitive test equipment in order to be able to measure the difference. This is because any pressure loss is due to FRICTION, which is a function of distance. Anyone who has had plumbing or firefighter training knows about friction loss to the flow over a given distance.
 

[Dusty MI]

[David G]

It would only take 1.7 PSI difference to push the the water 48" up the column and drip, so I think it is possible.