Abstract: A heat trace system (10) is used for heating water to prevent freezing in a conduit (20) while servicing an aircraft positioned at a passenger loading bridge (52). An upstream fitting (26) is attached onto the conduit adjacent to a building structure and a downstream fitting (48) is attached onto the conduit adjacent to the cab of the passenger loading bridge. A coated retractable coiled wire disposed within the conduit and cold lead wires (46) enter through the upstream fitting and leave through the downstream fitting. A low voltage solid state power control box (56) is in communication with the cold lead attached to the coiled wire inside providing regulated electrical energy for heating the coiled wire thus preventing freezing the water within in the conduit.

Abstract: A de-icing, snow melting and warming system is taught which utilizes a heatsink (20) consisting of a number of board strips disposed in a planer array positioned within a building structure between its exterior and interior surface. The heatsink board strips have a gap (24) therebetween in which a heating cable (42) is positioned in a continuous serpentine manner and held in place with loop clamps (44). A gap filler (48) encases the heating cable including the enclosed gap forming a homogenous closure. A low voltage power transformer (54) is attached to electrical mains providing electrical voltage reduction to the heating cable of 30 volts or less, and controls and self diagnostics regulate the power and detect anomalies within the system.