In my search for the fresh water drain I read some other threads and found the hot and cold water low point drains on my 2013 Solera.
They are located on the left side of the entrance steps. I thought they were glued by the insulation spray around the area but there was no problem removing the caps ... they will drain your lines.
"Unfortunately" I currently live in San Diegoi and will probably never use this drain again
Attached is an annotated photo of the drain plugs ... the picture doesn't show it but if you look real close on yours one should be colored red and one colored blue.