HYDROGEN PRODUCING DEVICE AND CONTROL METHOD THEREFOR, AND FUEL CELL SYSTEM

A hydrogen generator (100) includes a reformer (1), a CO remover (2), a first desulfurizer (3a), a first heater (4), a second heater (5), and a controller (6), and the controller is configured to start the operation of one of the first heater and the second heater, then stop the operation of the one heater, and then start the operation of the other heater.