The efficiency of your refrigerator goes down because of dust build up on the condenser coil. So, these coils need to be cleaned once in a while to keep up the refrigeration efficiency.
View of the condenser coil under the fridge. (outside panel removed)
Before you clean the coil, fully disconnect the fridge from all power sources. Disconnect all lines including any water supply pipes. Move the fridge to a secure location for easier cleaning.
Locate the condenser coil.
In modern refrigerators, this is underneath the refrigerator. In older refrigerators, the coil is on the back. Sometimes the coil is located inside a panel. So, you might have to remove the panel in order to access the coil. Make sure you read the refrigerator’s maintenance manual to locate the condenser coils. Use a flashlight to locate the coil and dust.
Use a refrigerator coil brush.
You can also use a paintbrush to clean the coil. Using a refrigerator coil brush makes this cleaning easier. These are long brushes that can penetrate well inside the coil and gives a good clean.
Vacuum the coil and fan.
Once the coil is brushed, do a vacuum to remove any visible dust particles. Take care not to break any parts while brushing or vacuuming the coil. Vacuum the refrigerator fan too if that’s accessible. There might be dust accumulated on the fan blades. Give it a good vacuum and you are done!
If you are not sure how to clean the refrigerator coil, it is better to approach a professional who can do this for you. Make sure you clean this coil at least once a year to keep your fridge running at full efficiency.