Originally Posted by JCWDCW
Hardly the solution for an RV, but you can install a small pump under the sink at the end of a long run, that circulates water from the HW tank back through the cold water line intil it senses the hot water. Basically requires that you switch it on and wait for the HW to get to the pump at which point it shuts off and HW is now up to the bathroom. Really great idea for a situation that takes 2 or 3 minutes to get HW through the lines
Interesting....do you have a link or a name? Not sure how I'd get to my pipes close to the shower valve. Lines run under floor and inside a wall, but might be worth looking into.