I just had a look at your fridge on you tube. Looks like a small home fridge. All bad , not enough insulation, huge front loading door . To get an efficient fridge on a
boat that dosent eat your
batteries they have to be well insulated, R20 or even better R30. That works out to be around 6 inches of wall thickness , by the looks of the CR1110 it has 1 or 2 inches of insulation . Also they should only be top loading so you don,t loose all the cold inside every time you grab a
beer . So this computes into more BTUs of heat getting into the fridge then the small compressor can take out.One thing about living on a
boat , our ideas of a fridge has to drastically change . Land based fridges have massive compressors that are driven from the an infinite amount of
power that can be put out by your outlet. Put an amp meter on your home fridge and take a look at the power it takes ! Yikes !! So it can over come the poor insulation.
So sorry no "magic bullet"