Welcome to the forum GrimlocKing. So lets find out more first:
Do you lose both hot and cold water pressure in all bathroom fixtures when on shore water? When you return to on board fresh water (via your pump) does the pressure return to both hot and cold bathroom fixtures (not changing any slide positions)? Do you notice the pressure change when putting out the sofa slide or the bedroom slide? Shore water could more likely be affected by your bedroom slide based on floor plan.....but the kitchen stays working....strange depending on plumbing routing.
The 31S floorplan (if I looked at the correct one on line) has bathroom and shower cross aisle and shower and kitchen on passenger side. So it is odd that when the problem occurs the kitchen runs fine but not the bathroom/shower fixtures. I would think the hot/cold plumbing would run from bathroom (on driver side) to shower and kitchen (on passenger side) but the Thor plumbing diagram should show that.....assuming it is “as built”.
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