How To Replace the Defrost Heater
The defrost heater is located at the back of the freezer. It may be necessary to remove obstructions such as the contents of the freezer, freezer shelves, icemaker and the rear inside panel of the freezer.
Before replacing the defrost heater, unplug the refrigerator to avoid an electrical shock hazard.
The rear panel may be held in place by retainer clips or screws. Remove the screws or depress the retainer clips with a small screwdriver. If you must remove the shelf, first determine if any screws must be removed. Next, carefully inspect the seams use a putty knife to carefully split them. The plastic is easily damaged and it is best to warm it first with a warm wet towel. After separating the seams, lift and pull the shelf out of the freezer.
There are three primary types of defrost heater elements; exposed metal rod, metal rod covered with aluminum tape or a wire coil inside a glass tube. All three elements are tested in the same way.
The heater is connected by two wires. The wires are connected with slip on connectors. Firmly pull the connectors off of the terminals (do not pull on the wire). You may need to use a pair of needle-nose pliers to remove the connectors. Inspect the connectors and the terminals for corrosion. If the connectors are corroded they should be replaced.
Depending upon the type of defrost heater, it is held in place with clips or some other method. Remove the old heater. If your heater has a glass tube, do not touch the replacement with your bare fingers. Skin oil from your fingers will cause the heater to burn hot, resulting in damage to the heater and/or your freezer. If you do touch it, clean with a clean cloth or paper towel and rubbing alcohol.
Install the new defrost heater, reconnect the wires, replace any access panel you may have removed and plug in the refrigerator.