Delta Shower Head flows when off

What are we doing wrong? Brand new Delta shower/tub combo. We have capped the bottom (tub) as this will be a shower only. Once we get it up, turn knob to off position, the shower still flows. Not a drip, but a good flow. It is off. We replaced springs and washers just incase, with no luck. Why won't it stop flowing?

 

If that is PVC schedule 40, it is not allowed for use indoors. Also, plastic 'female' fittings are not allowed to screw on to metal 'male' fittings.
My guess is that you do not have the cartridge inserted into the valve body with the two notches aligned with the detents in the valve.

 

My guess is that you do not have the cartridge inserted into the valve body with the two notches aligned with the detents in the valve.[/QUOTE]

I don't think it is a cartridge issue. It snaps into place perfectly and the metal ring fits as it should. If the cartridge was not seared properly, the metal ring wouldn't tighten.

 

The cartridge has o-ring sockets that fit into recesses in the back of the valve body and can fit in only 2 ways and both are correct and will only affect the hot/cold sequence.

Quick read through the manual of a 14 series suggest replacing the seats and springs and checking the condition of the lower o-rings. If that doesn't solve it then replace the cartridge.