How large is the refer, likely three or four door. I would not rely on a single battery. We did a JC Refrigeration 12 volt compressor conversion on our Dometic RM2862, we have not yet needed to last long on battery, but expect that our two Interstate SRM27 deep cycle batteries will run us overnight. If you without shore power there are basically two situations:
1. Warm/hot outside no need for furnace, lots of run time for compressor.
2. Cold outside, furnace draw high, and refer draw low.
Russ & Paula the Beagle Belle.
2016 Ram Laramie 3500 Aisin DRW 4X4 Long bed.
2005 Copper Canyon 293 FWSLS, 32' GVWR 12,360#
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