An image forming apparatus operable in a first mode operated in a first voltage and in second mode operated in a second voltage lower than the first voltage. The apparatus includes a power source device, cooling fan, temperature detector, controller and a recovery circuit. The recovery circuit outputs a signal when a detected temperature of the temperature detector is equal to a predetermined temperature or higher. The controller includes a port for detecting the signal outputted from the recovery circuit in the second mode. Upon detecting that the signal is inputted to the port from the recovery circuit in the second mode, the controller switches the power source device to in a first output mode for outputting the first voltage from in a second output mode for outputting the second voltage and operates the cooling fan to cool the power source device.