Guys, I no longer have the Sandpiper, but my new Montana has the Whisper Quiet Cool AC system and I too am having problems with keeping the temps down. Last week in Myrtle Beach it was 95* and the rig was only 82* on the inside. I was livid. I've had the units off at the dealer to check the ducts, voltage and fan speeds. Nothing was out of line. During the trip, I kept on playing with the system. What made the most difference was taking the vent covers off of the vents! The covers have louvers that direct the air flow along the ceiling which is warm. Without the "quick cool" like we are all used to, these do not have them. With the covers off, the air flow is to the floor is much greater and the rig will cool better. After taking my covers off, we all noticed and increase in air flow and lower temps by 5-7*. I'm not happy at all with the new style system. Whether I bought a new Sandpiper of a new Montana, that was the system I would get. My main gripe is that my old Sandpiper 365SAQ sat behind me at the beach as my friend now owns it, kept the air temps about 8-10* lower than I was able to keep the Montana. I know it is not aesthetically pleasing, but take the vent covers down and see if it makes a difference with yours. Good luck.
2012 Sandpiper 365SAQ weighing @ 15k, Onan, 2nd air, slide toppers, TST
2013 F350 6.7L Lariat 4x4 CC DRW,Viair 1007, Ride-Rites, Edge CTS, B&W
2001 Chevy 3500CC DRW 4x4, 8.1L, 4.10 gears w/ Detroit TrueTrac
2001 Ford Excursion Limited 4x4 7.3L,V/B Spring Mod, ProComps, Hellwig Swaybar, & other 'Necessities'