I would like opinions on whether, after reopening the shutoff valve at the cold water inlet line to the water heater following completion of repairs, there is a duty to tighten the packing nut to eliminate the possibility, however remote, of future leaks.
Leaky. Are you asking, if it aint broke, do I break it? A stuffing box is there to tighten if leakage occurs the same applies with “o” rings you replace them if they leak. If the control valve was tight to turn off maybe the stuffing box had been previously overtightened & in that case you would have a duty to service & repack the stuffing box. Why would any body tighten the stuffing box every time it was turned off? that would cause overtightening & premature failure. Bob