Assuming you're referencing a Suburban 10DE water heater, the manual provides this note:
The thermostat on your water heater is not adjustable. It is a temperature
sensing limit designed to maintain a water temperature of 130°F (54°C).
Water temperatures over 125°F (49°C) can cause severe burns instantly
or death from scalds; therefore, be careful when using hot water.
Children, disabled and elderly are at highest risk of being scalded. Always
feel water before bathing or showering.
However, I also read a Suburban Service Manual that listed a 130 degree element as being "Standard" and a 140 degree element as being an "Option". I personally agree with okcnewbie that "hotter is better". I had replaced the element in our previous heater that was rated at 130 degrees and the gas came on regularly. Our new Suburban only lights the gas when the DW takes a long shower or runs the washing machine on hot. I do not know the rating of our current element. My personal preference is to limit use of propane since it costs more than using the electric shore power.
Just don't exceed the 10 AMP limit AC limit!
Bob Bowers (Surprise, AZ)
2003 Alpine Coach 40' FDTS
2014 Jeep Cherokee Lattitude