FYI, we toured the FWC facility with Stan in the last 2 weeks, and Stan said they are not using the "combi" unit because it is too big, so they are using separate Truma heater and water heater units. I was dismayed to hear this, as the benefits of the combi are smaller size, and higher efficiency. I wanted to install a combi in my Puma build, but discovered the same thing, the combi is big.....