For estimating refrigerator temperatures, look to the fluids stored near the back of the cabinet. Ice crystals in any liquid in the cold storage compartment indicates the temperature is too low. Do not put hot dishes directly into the refrigerator or freezer. Set hot dishes aside until they are near room temperature, then store them in the refrigerator. Cover foods, especially liquids, placed in the refrigerator.
Uncovered liquids evaporate in the refrigerator causing higher power use.
Mark freezer storage items to minimize open-door time. If practical, consolidate freezer or refrigerator storage so that you can turn off the spare unit. If spare refrigerators or freezers can be disconnected for only a few months per year, significant savings will result. Dormant storage will not damage a healthy unit. Full freezers use less power.