This is a very popular question, and it is an important one. Temperatures that are off only a couple of degrees can impact the efficiency of the appliance. First and foremost, if your fridge and freezer only have dial settings, invest in an appliance thermometer so we can get these settings dialed in.
Refrigerator Temperature Settings
Most refrigerators have a small dial with numbers for you to adjust the settings. More modern refrigerators have a temperature reading, but that was not always the case. Ideally, the fridge will be between 35 and 38 degrees Fahrenheit. Grab your appliance thermometer and sit it inside the fridge (ideally, get one that can stick to the wall or hang from one of the racks), then close the door and give it time to get the reading. Once you have the reading, you will have a better idea of the number settings and can adjust the fridge to the proper temperature setting.
The placement of the fridge also plays a role on how effective it runs. You never want the refrigerator next to appliances that kick off heat, such as the dishwasher or stove. You also need to ensure you have enough space around the refrigerator for the proper air circulation. One thing you can do on a regular basis is to keep the coils on the back of the fridge clean so they are not working harder to maintain the temperature.
Now that you have a thermometer inside the fridge, make sure you check it regularly to ensure the temperature is consistent. If you the temperature moving around, we would advise you to call an appliance repair technician to give it a check-up.
Freezer Temperature Settings
The ideal temperature setting for your refrigerator is 0 degrees Fahrenheit. If you see your freezer warming up from time to time, this can result in freezer burn and foil spoilage. Something else to keep any eye on is if you start to see frost build up inside the freezer. This can, however, also be the result of putting food that is too warm into the freezer. If you have not done that and you are seeing frost regularly build-up, it is probably time to call an appliance repair technician to have a quick look.
PM Your Fridge and Freezer
We cannot stress enough that performing the most basic maintenance tasks on your fridge and freezer will not only keep your food fresh, but it will also expand the shelf life of your appliance.