I installed a kohler Shower/Bath valve in my upstairs bathroom. For some reason when we run the downstairs bath a really loud banging vibration starts and water starts coming out of my upstairs new Kohler Faucet when turned off. I tried bleeding the lines and still have the problem.

Hi Kimber

What valve(s) did you shut off to install the new shower/bath valve? Did you just shut the main water supply off or did you shut off separate valves (hot and cold)?

Finally, what happens when you flush the downstairs toilet or turn on the downstairs sink faucet? Let me know more, OK?

Mark