We have a 2012 29BHS also. The water pump is located in the back of the trailer under the streetside lower bunk. To get access, remove the mattress and piece of luan under that mattress. This gives you access to the water heater and the storage compartment at the back of the trailer.
Catsense? We found out how to temporarily disable it just by turning it off and on several times.
Here is what I found on the Lippert site on how to permanently disable it:
Now if only we could get that tanklesswater heater to give us consistent temperatures!