Methods are provided for controlling a refrigerated dryer of a gas compressor system. In an aspect, a control system, including a controller and a flow sensor, selectively operates in a power saving mode in which the controller shuts down a refrigerant compressor included in the dryer system when the flow sensor indicates that no compressed gas is flowing through the dryer. The control system uses input from a temperature sensor to determine whether to activate the compressor regardless of the flow of compressed gas through the dryer.