920338 Nordyne DEFROST BOARD

Product Description

The 920338 defrost control board is the OEM adaptive defrost module for Nordyne and compatible heat-pump condensing units. It monitors outdoor coil temperature via a sensing input, applies timed or sensor-driven defrost cycles, and drives the hot-gas solenoid or reversing valve to clear frost buildup. Housed in a sealed enclosure with quick-connect terminals and an integrated mounting bracket, it includes on-board diagnostics and configurable timers to optimize energy use and ensure safe operation.

Kit Contents

• 920338 defrost control printed-circuit board with factory-mounted harness connector

• Mounting bracket and hardware pack

• Quick-connect terminal pins and wire nuts

• Detailed installation and wiring instructions

Key Features

• Adaptive defrost algorithm adjusts cycle frequency based on run time and ambient conditions

• Configurable default timers (max defrost, minimum off, termination) via onboard jumpers

• LED status indicator for diagnostic modes and fault codes

• 24 VAC control inputs for coil-sensor and air-temperature signals

• Outputs for hot-gas valve or reversing-valve coil activation

• Automatic sensor-open/short detection with fail-safe lockout

• Sealed enclosure rated NEMA 1 for indoor control-compartment mounting

Compatibility

Fits Nordyne, Coleman, Concord, Ducane, and Intertherm heat-pump condensing units originally equipped with a 920338 or equivalent defrost board. Always verify existing board part number, harness style, and sensor wiring before ordering.