Abstract: An end cap for a defrost heater is shown in which a positive locking mechanism is used to allow the lead wires to extend downward from the end cap. This increases the end cap's resistance to moisture and simplifies the design, thus lowering manufacturing cost. The end cap is also shown with a vertical vent that overlaps the retaining bore to significantly increase venting area over prior designs. The positive locking mating tab and the vent are located in two separate, but adjacent, vertical passages.

Abstract: A defrost heater for a cooling appliance, such as a refrigerator or freezer, which has multiple sets of evaporator coils includes a formed glass tube enclosing an electrical resistance wire. The glass tube is substantially bell-shaped, the opposite ends of which are mounted below one set of evaporator coils. The heater includes upwardly curving portions extending upwardly in the clearance between two of the sets of evaporator coils and a downwardly facing portion connecting the upwardly extending portions of the tube which lies adjacent to the lower edge of an upper set of evaporator coils.

Abstract: A defrost heater for a refrigerator, freezer or other appliance having evaporator coils upon which moisture condenses and freezes includes a glass tube having an electrical resistance heating wire within the tube. A pair of connectors on opposite ends of the tube support a conductor for supplying electrical energy to the resistance heating wire. A spiral vent path in at least one of the conductors circumscribes the surface of the conductor and engages the outer surface of the tube to thereby provide an elongated, circuitous vent path which permits venting of air within the tube as it is heated, but prevents moisture from being drawn into the tube. A resilient sealing member defines a bore receiving the conductor to prevent moisture from entering the connector around the conductor.