I suggest you locate the drain valves and close them. They will be located inside the trailer near the point the red and blue hose exits the trailer. They may be very difficult to locate as ofter they are behind small wood walls where you can not see them. There may be more than 2 in the system. Also, make sure you close the outside shower faucets and replace the PUR water filter. They may be the push-pull type or the screw type.
Jim & Eileen
Silverado 1500 Crew Cab, 5.3 ltr, prodigy controller.
2009 Rockwood 2604.
Running mates Max & Kate Chihuahua's
Hobie Kayaks on Thule rack on truck
Retired Army EOD