New Bath/Shower Valve Problems

[TWB]

I just installed a new Kohler bath & shower faucet. The system is a single handle pressure balancing valve also new Kohler. Here’s the problem. When I turn on the water to full hot everything works fine, the water comes out the tub spout and no water comes out the showerhead. But as soon as I turn the handle back down to warm or cold, water starts coming out the showerhead and continues out the tub spout. The pressure out of the showerhead is not full pressure but about ½ flow. Does anyone have and ideas? Thanks for the help in advance.

[jadnashua]

What kind of pipe and size connects to the tub spout and the shower head? What is the distance from the valve to the spout? What kind of divertor is there to direct the water to the shower from the tub?

Using something like pex or cpvc to make the connection might create too much of a flow restriction since the interior diameter is smaller than copper. Having the max/min distances beyond the spec can also create this kind of a problem.

[Plumber Jim]

Are you sure you piped it correctly? you may have hooked the hot to were the spout should be and the cold were the shower head should be. or the other way around.

[jadnashua]

Some valves, even though they have two outputs, are not designed to have both hooked up. You may need a twin-el on the one outlet verses using both ports. The instructions should say.

[TWB]

The pipe I used is ½” copper. The distance from the center of the tub spout and the center of the valve is 8”. The manual recommends 7” – 18”. The valve is piped correctly and the manual shows both outputs can be used. I am still scratching my head on this one. Do you think the pressure balancing unit could be bad? Again thanks for the help.

[jadnashua]

On some, while you can use either output, you can't use both. If there is any restriction in the tub spout, if you have enough pressure and flow, it can't all get out of the spout and will back up into the shower riser. Are you sure it says BOTh can be used SIMULTANEOUSLY?

[Plumber Jim]

did double check and see if you piped it correctly? the top connection will say top or shower on the brass in the back. If you have the valve turned 90 degrees then what you are describing could happen.

[TWB]

I doubled check the valve. It is installed right side up. The manual does say "Only connect a non-restricted flow spout to an uncapped spout outlet. Do not connect restricted flow devices unless the shower outlet on the valve is capped." My tub spout has a divertor but is not a low flow spout. Any thoughts? I removed the tub spout completely and tested it, with the same results, a low flow of water will come out of the shower head unless full hot is on. There is good flow coming out of the pipe nipple/tub spout no matter where the valve handle is turned. Is there a chance the pressure balance valve is faulty?

[Plumber Jim]

Could you show us a picture of the valve front and back?