The Trane CNT04364 (21C140501G38) Defrost Control Board is a reliable and essential component for maintaining peak performance in your heat pump system. Designed to manage defrost cycles efficiently, this board ensures that outdoor coils remain ice-free during low-temperature operation, improving both energy efficiency and unit longevity. Key Features Factory OEM replacement control board for precise compatibility Controls defrost timing and activation based on temperature and run time Enhances system efficiency and performance in cold climates Plug-and-play wiring harnesses for easy installation Compatible with a wide range of Trane and American Standard units Specifications Part Numbers: CNT04364, 21C140501G38 Function: Defrost control Voltage: 24V Cycle Control: Time and temperature-based defrost logic Application: Heat pump systems Compatible Models (Short List) 4WCZ6048A1000AA 4WCY5042A1000AA 4DCZ6060C1115AA 4WCX3036A4000BA 4DCY4060A3120CB 4WCY5036A1000AA 4WCC3060A4000AA 4DCZ6048A1096BB 4WCZ6060A1000BA 4DCY4042C1090AC Why Choose This Item Choose the Trane CNT04364 Defrost Board to keep your heat pump system running reliably through the winter. With OEM-grade quality, proven durability, and broad model compatibility, this board is the ideal solution for replacing a failed or outdated defrost controller?ensuring your home stays warm and your system operates efficiently.