I added an adjustable thermostat to our Atwood water heater. It took about five minutes to replace the non-adjustable thermostat. It's so nice to no longer have scalding water. Ours is a ten gallon heater and we haven't had any issues running out of hot water with showers.
Just curious won't you have less hot water and shorter hot water run time? As the HW temp comes down, won't that allow for quicker depletion when the cold water mixes thus cooling the hot water quicker?
Salada, you are correct that lowering the temp will deplete the amount of hot water available faster, assuming you adjust the temp mixing valve to the same temp as you have in the past. I don't mind the hot temps as I can take a longer shower. If I had small kids camping with me, that would be another issue.
Stan and Terri
Oak Harbor, WA
2008 Chevy 2500HD D/A
2007 Cruiser CF30SK
Glide Ride Pin Box
Reese 16K Slider