[bandnew]

In my 2010 3600 open, the water heater is behind the salon back rest cushion wall, under the shore power panel. You have to unscrew panel behind your back rest. If you have the Bose system, you’ll need to manhandle that cubby out first. 

Fresh water pump is there. Note that you likely have two, one for inside which is located close to the water heater, and your fresh water wash down one in your hatches close to the transom.