My 25' with one a/c will keep it under 80 degrees. Ain't brought it to Texas yet but that was the case when it was 117 in Nevada and also about 100 in gerorgia which was real nasty.
I'm in Bama and often see very hot temps with high humidity. My single 13.5 keeps my trailer very comfortable, can hold 72 on a sunny 95 degree day. My trailer is white which I'm sure helps.
I had my '18 30 FB in the driveway this weekend (just north of Houston) with temps in the high 90's with a heat index of about 400. Interior was at 70 as the sun came up and by the peak of the afternoon it was about 81 inside according to the thermostat inside temp reading. It didn't feel that warm but it wasn't keeping up. This is on a 30 amp connection with only 1 ac unit running. I'd say go for 2 units just for the extra power to cool the trailer down after a day of travel in the hot sun. If not it will take awhile to get the interior close to comfortable.
I have a 25' FB Classic, we have a hard time getting it cool. Outside 90 inside 79 or 84 I checked out flow air temp at 52 degrees. The fan is on auto but it stays on low, , are open, blow down open, filters clean, only goes to high when I move it to high. Thinking about replacing it with a 15K The elect C/B 20amp 20gaue wiring.
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