hot water bypass
I go in at the end of the counter, open both drawers, or take them out.
You can see the tank. Three valves, two in the waterlines and one on a cross connection. Cross connection is before the inline valves, so if the two water line valves are lined up with the water lines, they should be open. The crossover line valve should be closed. IE looks like a cross. This means the tank will fill with water. After filling turn on your choice of heat.
Hope this helps. Our trailer is a 2014, 3008w