AIR SUPPLY SYSTEM

An air supply system comprises: a compressor that has a load operation mode and an idle operation mode; a desiccant that is configured so as to remove moisture from compressed air sent from the compressor; a first solenoid valve that is configured so as to selectively switch the compressor between load operation mode and idle operation mode; a drain discharge valve that is connected to a branching channel that branches from a connecting channel, said drain discharge valve being configured so as to open the branching channel in accordance with a second solenoid valve being driven and so as to seal the branching channel in accordance with the second solenoid valve not being driven; and a control device that is configured so as to control the first solenoid valve and the second solenoid valve.