If you camp in winter weather, those waterlines will freeze. Happened to us last year with the2017 40D.
I'm just finishing up my freezing weather package now preparing for our Feb. trip to AZ.
I put a heattape between the two water lines and secured them together with small wire tie's. Ran the heat tape in to where those braded lines connect to the pex. I drilled a hole in the front of the opening so the 120V plug could go to the front compartment plug. The thermostst has hang out where it's cold. I cut two 4" thick foam pads to fill in the space top and bottom with a notch cut out for the lines.
My last piece I'm working on now is a sock that will extend from the bottom of the slide to inside between the foam blocks, and will enclose all the lines to retain theheat tape heat. The sock will have a Velcro strip along it's length so it will wrap around the lines and attach together.
2019 Fleetwood Discovery LXE 40M w/2012 CRV toad