The fresh food compartment of your refrigerator should be kept between 37 and 40 degrees. The freezer compartment should be 5 degrees. A separate freezer should be kept at zero.
To test the temperature of your refrigerator, place an appliance thermometer in a glass of water in the center of the refrigerator. Read it after 24 hours. To test the freezer compartment, place the thermometer between frozen items. Read after 24 hours.