We lived in the Palm Springs area with some months of 90 to 110 temperatures, I installed 12vdc fans on the exhaust vent on the roof of the RV and had to adjust the thermistor down, stuff started freezing in the bottom of the refrigerator, you can purchase 12vdc, make sure that you install a fuse and a switch to turn them off when not needed.
It also helps if the wall where the fridge is is not exposed directly to the heat of the sun some shade helps, there is 12vdc power at the back of the unit.
navegator