o1, this topic usually turns into one of those "So's your old lady" arguments that no one seems able to agree on. I've posted on this topic many times but gawd help me if I can find one of them now--so here goes.
While my heater is the L5 and not the L 10 there will be size differences in the unit but the exact same mechanism of operation still apply. In short, I built a closed steel locker to house the heater in. Air of combustion (and cooling) enter from under the bus while exhaust (and heat) exit through a port high up on the side of the body No air of combustion comes from inside the bus and no ehxaust enters the bus. I installed a sealed access plate to allow for temp/flow adjustment and battery replacement and provided a remote placement of the on/off switch. My unit has been operating flawlessly now for nearly 5 years. The only "improvement" I've made on my installation was to install a recirculating system to prevent the endless on/off cycle of the heater and to conserve water while waiting for it to heat up. Of course since the recirculation of heated water back into the fresh water tank eventually raises the inlet temp at the heater -- especially when the tank is low, it is necessary to install a thermocouple switch of the desired temp at the outlet from the water heater to prevent scalding etc.
Here is where the "Ah pisha it'll never get hot enough to need all that metal surround" starts. Remember that wood begins to char at 450 degrees F after a few hours ignites. It immediately ignites at 700 degrees F. With the heater rated at 37,500 BTUs, those exhaust temps are easily reached.
Jack
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