Automotive air-conditioning system

An automotive air-conditioning system according to an aspect of the present invention includes a bypass passage through which cool air flows, bypassing a heating heat exchanger; a hot air passage through which hot air passing through the heating heat exchanger flows, the hot air passage has a downstream portion curved toward the bypass passage; an air mixing chamber located at a confluence of the bypass passage and the hot air passage, for mixing hot air and cool air; at least one front outlet passage diverging from the air mixing chamber toward the front side of a passenger compartment; at least one rear outlet passage diverging from the air mixing chamber toward the rear side of the passenger compartment, the at least one rear outlet passage has an upstream portion arranged along the hot air passage; a communication path configured to connect the hot air passage to a middle portion of the at least one rear outlet passage; and a door configured to open and close the communication path.