Which components are considered the outputs of the Trane defrost control?

The correct choice identifies the components that are outputs of the Trane defrost control system, which is essential for the operation of heat pumps in preventing frost build-up on the outdoor coil during heating mode.

In the context of heat pump systems, the defrost control activates specific components to ensure efficient operation during colder conditions. The condenser fan motor, compressor, auxiliary (X2) backup heat, and the changeover valve are all integral to the defrost cycle. The condenser fan motor operates to stop airflow across the outdoor coil, allowing for the melting of accumulated frost. The compressor facilitates the refrigerant flow necessary for the heat exchange process, while the backup heat provides alternative heat sources when needed. The changeover valve allows for the switching between heating and cooling modes, which can be crucial during the defrost process to reconfigure the system's operation appropriately.

Other options do not represent direct outputs of the defrost control. The compressor and indoor fan motor, for instance, are critical components of the system, but they do not specifically operate in responding to the defrost cycle directives. Similarly, the outdoor coil and refrigerant lines are components of the overall heat pump system, not outputs of the defrost control. The thermostat and pressure switch are also essential