To test the temperature of your refrigerator, place a thermometer in a glass of water, and check it the next day (or after the fridge has been closed for at least eight hours). To test the temperature of your freezer, place a thermometer between two frozen foods; then, check it after eight hours. Note: It can take up to 24 hours for a temperature change to take effect. Do you want to save even more? According to the U.S. Food and Drug Administration, refrigerator settings can safely be set as high as 40 degrees Fahrenheit, while freezer settings can be set as high as 5 degrees Fahrenheit. Note: If you have a newer refrigerator, it may have automatic moisture control, which eliminates exterior condensation without the use of a heater. To cut down on the amount of time the freezer door is open, consider  creating a freezer inventory list that you can stick on the door. As long as you keep it updated, you won’t have to spend a bunch of time digging around in the freezer.