When shopping for a rooftop unit, one of the first specifications you'll encounter is BTU (British Thermal Unit). In simple terms, BTU measures how much heat an air conditioner can remove from your RV in one hour. Higher BTU ratings generally provide greater cooling capacity, but bigger is not always better. 

Choosing too few BTUs can leave your system running continuously while struggling to maintain the set temperature. Choosing too many can cause short cycling, which is when the unit cools quickly and shuts off before properly removing humidity from the air. This can reduce efficiency and make your living space feel damp and uncomfortable. 

That being said, BTU ratings are less of a factor when discussing variable speed air conditioners. These units adjust their cooling output as needed, which helps maintain more consistent temperatures while simultaneously