I don't know what brand fridge you have but Samsung says our RF197 will run okay on a modified sine wave inverter. We did that for a couple of years with a 1000 watt one that came with the fiver without any problems. I just wasn't comfortable with it so I changed to a 1000 watt pure sine wave, upgraded the wiring from the batteries to the inverter to a heavier and recommended gauge, added a circuit breaker between the batteries and the inverter and installed a transfer switch that automatically changes from battery to shore power and vice versa. May have been totally unnecessary but I feel better about it.