refrigerator

Do not park the refrigerator next to your stove, a heater or an uninsulated wall, as this would reduce its efficiency.

Do not put hot food in the refrigerator, let it cool down to room temperature first. It will also prevent bacterial growth if you leave it out for about 20 minutes.

If you do not own a frost free model refrigerator, frost on the cooling panels will reduce the efficiency. Defrost it once the frost goes beyond 1 cm.

Do not set the control temperature of your refrigerator too low, as it just waste energy to maintain the setpoint.

A refrigerator operates at peak efficiency when filled. Once you open the door, there will be less cold air to move out of the fridge, but more cold goodies which will keep the cold inside.