Residential Fridge battery run time

willald wrote:
This is something I'm curious about also, as we plan to do more and more boondocking, and trying to get an idea of how long our frig (Whirlpool 120V residential model) can keep cool without hookups.

Here are the specifics for ours:
Frig says it uses 2.5 amps, full load
RV has 6 GC2 (225 Amp/hour, 6 volt) coach batteries
Xantrex 2000 watt inverter/converter powers the frig when not hooked up to electricity

Based on this, my rough estimate is that we should be able to keep the frig cool for about two days without depleting the batteries too badly. Three at most, but of course it also depends on what other loads are put on the coach batteries. Does this sound accurate?

Also thinking, if I was to run the generator for 2 or 3 hours each day as well, we should be able to last almost indefinite as far as frig is concerned. Thoughts?

My thoughts and calculations show way less than 2 days. The 2.5 amps @ 120 is 25 amps @ 12 volts. You have 6 x 225 AH @ 6 volts which is 675 AH @ 12 volts. Draining battery bank to 50% gives you 338 AH @ 12 volts. 338/25 = 13.5 hours. Your inverter will cost you about 10% so somewhere around 12 hours. So you will need to fire up the generator about every 12 hours. You need to replenish 338 AH. If you have a good sized charger of about 50 amps that will take about 7 hours to reach a partial full charge. So 14 hours of generator time per day. Every few days you should consider running the generator full time for 24 hours to bring the batteries up to a full charge.

Of course this is based on the compressor running full time. Run time is a big variable and could be much less if the ambient temps are cool, no warm items are added and you don't open the door frequently or for long periods. I would not count on dropping below about 60% compressor run time. That would cut your gen time by several hours a day but probably no less than about 10 hours.