Most modern freezers don’t need to be defrosted, but should be washed out and cleaned periodically. Following are steps for defrosting freezers that need it -generally when ice builds up to a thickness between 1/4 inch and 1/2 inch.
4 Do not use soapy water to clean the freezer. Never chip at freezer ice with ice picks or other sharp instruments. If you use a hair dryer to melt ice, be aware that there is a risk of electrical shock if the dryer comes in direct contact with water or if you are standing in water on the floor.
Remove ice in the freezer compartment. This can be done by: a) letting the freezer door stand open until ice melts; b) putting a pan of hot water in the freezer compartment and closing the door, then checking for melting ice and reheating the water every 10 to 15 minutes; c) using a hair dryer by aiming warm air at ice in freezer until it melts.
Turn the freezer back on, close the door and let run for 10 to 15 minutes before returning food to the freezer.