My old XLV 1999 #539 Marathon is equipped with OTR and 3 Cruisair units, 2 X 4000w trace inverters, 6x 250ah lithium batteries, we added 2 MPS low profile 24v roof top units, I came out to the conclusion that if I build a new coach I will equip it with only 24v roof top units, maybe 3 or 4 but nothing else. We run 2 all night and our battery bank goes down only about 20%, they are quiet and ultra efficient, hot air goes up not down so conditioning the air is much easier, this is the way they look.
The question is: why have so many systems? 24v units will run on the engine alternator on batteries, on shore power with the bat charger.. My 2 units are doing a phenomenal job to keep us comfortable, we will be covering our roof with solar panels to make it even more interesting. Generator is charging our batteries in a record time..
We changed out refrigerators by dual voltage 24v 115v but most of the time they run on 24v..
Now changing the oil on our generator is not as often.