Most RV's that exceed 33 feet or so come with two AC's, and the trend now for anything approaching 40 feet, is three AC's. Unfortunately because of power restrictions, RV's with 3 AC's have lower capacity units, so other than better air distribution, cooling effect is only a marginal improvement. Problem with any RV is the lack of insulation in the walls, which are very thin to start with. Parked in direct sunlight, the heat load is intense.
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