After discovering I was unable to gravity fill the fresh water tank on our first outing, my dealer rotated the fresh water fill unit so the fill spout was relocated to an 11 o'clock position (originally 6 o'clock) putting the vent at 5 o'clock (originally 12 o'clock). In the original factory position, the inside hose from the fill spout to fresh water tank had to rise up and over the hot water tank, causing water not under pressure (not coming from a hose) to flow right back out of the fill spout. Rotating the spout to a higher position eliminated the rise in the hose. Using water containers with flexible pour spouts that curve up and into the new fill spout location during filling completed the solution.