Making a tub faucet into a tub/shower faucet

I am in the process of remodeling the bathroom on the house I just bought (built in 1958). As far as I can tell, the tub has the original 2 handle Price Pfister tub control. My intent was to replace the valve so as to add showering capability. When I ripped open the "wet wall" to gain access to the valve, I noticed that the PP valve had a 1/2" male brass plug screwed into the top of it. I thought to myself, "A ha! All I have to do is remove this plug and install a shower pipe with head and a new tub spout with built-in diverter knob, and I'm all set! I won't have to replace the whole valve afterall (which would be a pain due to an adjacent vent pipe)! The house designer or plumber must have decided not to install a shower head so as to save money." So, I've done all that, tested it out, and here's what happens:

1) When the water is turned on to a low or medium setting, water flows out the tub spout and everything is fine.

2) When turned to a higher pressure, water starts dribbling out the shower spout, even though the diverter remains in the down position.

3) At full blast, quite a bit of water comes out the shower head. When the diverter knob is pulled up, more water comes out the shower head, but there is still a lot coming out the tub spout.

I started thinking that maybe this valve was not intended to be used in a tub/shower combo mode like I've done. And that the plug was there in case you wanted to use the same valve for a shower (whereby you would install the plug where the tub spout would be instead). If that's the case, is there anything I can do to make this work properly? Or is the new tub spout/diverter defective maybe? It almost works OK, as I've indicated, and I really hesitate to replace the valve, as I've already installed backerboard over the valve. Simple fixes or ideas would be much appreciated!! thanks.

The valve body was designed to be used in tub, shower, or tub shower combos. The side effect you describe is to be expected. Today, in a tub shower combo, they will insert a flow restrictor in the outlet to the shower head to reduce that problem. You could fashion something in there. You could also make sure the house pressure is not too high, because that will agravate the problem.

jimbo said:

The valve body was designed to be used in tub, shower, or tub shower combos. The side effect you describe is to be expected. Today, in a tub shower combo, they will insert a flow restrictor in the outlet to the shower head to reduce that problem. You could fashion something in there. You could also make sure the house pressure is not too high, because that will agravate the problem.

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Thanks Jimbo, for the timely response!! I do have high water pressure here (over 90 when I checked it), and I suspected that might have been part of the problem. In the one month that I've been living here, my old garden hose has split open under pressure at least twice. At my old place it was fine.

I'm thinking maybe I could install a 1/2" chrome in-line valve between the shower arm and shower head to restrict the flow. That way I can tweak and fine tune the flow restriction. Might that work?

If your pressue is 90 pounds, it might be best to put in a pressure reduction valve and (probably) an expansion tank. THe tank is usually required because the reduction valve usually contains a check valve. This means that when you use hot water, the denser, smaller cold water that refills the tank eventually gets heated, expands, and has no where to go - it can create problems. The expansion tank prevents that. The weakest link in the system is usually the pressure relief valve of the hot water heater - it will weep until the pressure caused by the heating is reduced from the expanded hot water.

shower

They used to make a brass fitting called a ( twin ell. ) for that purpose.
It is used where you would normally use an elbow between the faucet and tub spout.
It's a restricter fitting.
It has three tappings.
The third tapping goes to the shower head.
Ask the oldest guy at the wholesale house and may be he can find you one.
You can do it all from the access door.....

valve

That second opening was for use if the valve was inverted for use with supply pipes coming down from the ceiling, or up from the floor. When that valve was used with a shower the elbow to the spout was changed to a "twin ell" and the shower pipe rose out of the rear of that up to the shower arm. When it was designed as a tub/shower valve, it had a restrictor device to limit the amount of water so it could not develop the back pressure and flow out of the shower when the tub was being used. The twin ell is still available and is used with a 3/4" inlet diverter spout. Sometimes the two come together as a unit.

hj said:

That second opening was for use if the valve was inverted for use with supply pipes coming down from the ceiling, or up from the floor. When that valve was used with a shower the elbow to the spout was changed to a "twin ell" and the shower pipe rose out of the rear of that up to the shower arm. When it was designed as a tub/shower valve, it had a restrictor device to limit the amount of water so it could not develop the back pressure and flow out of the shower when the tub was being used. The twin ell is still available and is used with a 3/4" inlet diverter spout. Sometimes the two come together as a unit.

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Where might I find this twin ell that you speak of? Somewhere on the Internet or maybe at Home Depot? It sounds like that's just what I need!!

twin ell

Grohe makes one, or rather sells it because another company makes them for all the other companies. Home Depot would look at you like an alien if you asked for one. Any good plumbing or faucet repair supply store should have one. The pipe from the faucet goes into the "front" opening on top and the shower goes into the rear one. Be sure to get the correct diverter spout with it. A search for "twin ell" will probably produce several million hits.

hj said:

Grohe makes one, or rather sells it because another company makes them for all the other companies. Home Depot would look at you like an alien if you asked for one. Any good plumbing or faucet repair supply store should have one. The pipe from the faucet goes into the "front" opening on top and the shower goes into the rear one. Be sure to get the correct diverter spout with it. A search for "twin ell" will probably produce several million hits.

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I did a Googe search on "twin ell" and sure enough I did get a lot of hits. So, I don't don't think I'll have trouble getting one. There is also something out there called a "ejector tee diverter", which supposedly is similar to the "twin ell". It looks like it would be less trouble to install in my current situation. Unfortunately, I can't seem to find any available to purchase. Do you have any experience with these? Would a plumbing or faucet repair store have these as well?

Problem solved!! I picked up a twin ell at a specialty plumbing supply store. The "kid" at the counter had no idea what I was talking about, but a more experienced guy knew about it, and sold me one for about $7. Also picked up a new diverter spout with a 3/4" threaded input. Conected it all together, and it all worked properly! Except I have a small leak at one of the new solder joints at the back of the twin ell that's giving me a headache, mainly due to the poor accessability of the joint. Thanks to all who gave me the tips about the twin ell!! Nothing like free professional advice.