Originally Posted by jrctoby
Would it be any different between a 13000 and 15000 btu unit
BTU rating can be thought of as how many thermal units can be moved from inside the RV to the outside. Larger area, more BTUs; smaller area less BTUs. Overall, a higher rated unit will cool better.
An A/C unit has to remove heat from an area. Grab it and throw it outside. It's not just a matter of pumping cold air in, it has to remove the hot air.
Given the same size area, a larger BTU unit will cool a bit faster by removing more hot air in the same time frame.
My feeling is that unless you have really high heat and/or humidity, there isn't a big difference between the two although the 15K will possibly provide a perceived increase in cooling.