If you are going to add insulation to the floor you could have run the heater hoses on top of the insulation and under the floor material. Run it down the center of the isle where your feet hit the floor. Also saves holes in the floor.
Floor heat is good.
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2015 Promaster Sportsmobile
KB2ZE
Old retired IBM Engineer
Is the pictured tank only for your hot water? Also how do you fill it?
I assume you were asking about my pictures?
The tank is for cold water, hot water through the exchanger is instant so no need for a tank.
I usually just lift up the back bed cushion and fill the tank through the screw on lid on top, although I have a city water connection that can also fill it.