Re: Shower handles turn on their own
There should be a hose bib near the water main, do your pressure test there instead of tearing apart a wall.
Even with increased pressure, you shouldn't have an issue of the valves opening themselves. How much friction do you have when you turn the knobs? Can you spin the knob with a finger tip or does it take a fairly firm hand grip? If you can spin it with your finger, replace the packing around the stem.
I suffer from CDO ... Its like OCD, but in alphabetical order, LIKE IT SHOULD BE!!!