I have the 15k btu in my 21ssl. Not a whole lot smaller than your 233 when you factor in the size of the slide. It will positively FREEZE you out. We camped just last weekend, 100 degree days, and our spot was in direct sunlight from sunrise till about 7-7:30 at night. We have no reflectex or space blankets.
To be sure, the bunk ends were noticeably warmer than the main 'box', but only while the sun was up. But on the whole, I think I could hang meat in the thing. I didn't know if another 1.5k BTU in a/c would make a difference, but is sure seems like it does. My old class A with TWO 13.5K did not cool down like this one does.
FROG Member MO-0008-571 Since 2012
2016 Rockwood Signature Ultralite 8329ss (coming soon)
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