On the gas setting the fridge draw about 1.5 amps @ 12 volts maximum to operate the gas valve. So the added demand is about 18 watts.
I suggest turning *off* the breaker for the hot water heater before the next test of running the roof air.
I paid for an inspection on my first RV. It was money badly spent because I was not savvy enough to understand the results. If I had understood I might still have purchased the unit--but the testing was not comprehensive, and definitely was written in a "positive" manner.
