It is not necessary to apply a liquid cleaner to condenser coils on a refrigerator. Instead, the coils should be vacuumed with a vacuum hose and brushed with a vacuum attachment or dry paintbrush to remove dust and lint.
A coil brush can also be used to remove pet hair, dust or debris. When cleaning the coils, the refrigerator should be unplugged to reduce the risk of electric shock, and the base grille may need to be removed to access the condenser coils.
If the fan to the refrigerator is accessible, it can be vacuumed as well to help move air to the condenser coil without buildup of dust and dirt.