From day one of install, get 5+ gallons per minute through the tub spout, but about 1 per minute through the shower. No leaking from the spout when I pull up the diverter on the spout. Removed shower head, same flow. No blocks there. Also, the temperature response is terrible. Can move handle up and down slowly, but temps don't change much, then mid shower the temps will wander up 10 degrees on their own and settle back down. If the handle is at 6:00 when off, 3:00 is ice cold, 12:00 is barely warm and 9:00 it hits the stop, we have to have the handle between 10:00 and 11:00 to be at shower warmth. Worked great before the new valve and handle assembly. Any ideas on tweaks or adjustments I can look at to increase flow to the shower head and temperature responsiveness? Thank you!!!!

What is the stated gpm of the shower head? Have you removed the restrictor?

EDIT- I just reread and saw that you removed the showerhead and the flow out of the shower arm is low, so my comment doesn't apply.

When the new valve was installed could any debris have gotten into the valve from the piping connected to it? May need to take it apart and clean the water passages. Or return the valve as defective and get another one.



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