Why doesn't my refrigerator perform well on 120V AC?

You may have it on too low of a setting. The warmer it is outside, the higher the setting on the refrigerator will need to be maintain the proper cooling temperature. Norcold® refrigerators require a minimum of 115V on both sides of the fuse to perform as expected on AC. If that is confirmed and the unit is still not cooling well on AC, it should be taken to a local Norcold® dealer for further diagnosis.