A MD80 Captain refused an aircraft after the previous crew verbally reported cabin temperature near 115-120 degrees but did not write it in the maintenance log. Maintenance did not address an ineffective single pack cooling system.

Narrative

Aircraft first observed being surrounded by multiple fire trucks. Departing cabin crew reported excessive temperature with single pack operation. The remaining pack would not cool the aircraft at all and they; joined by the First Officer; reported continual temperature in the cabin of 115 to 120 degrees. In addition; the Captain reported excessive brake chatter and that the brakes had overheated - over 400 degrees Celsius. Ramp did not pass along his call to have fire trucks attend to the possible fire/explosion and he had to call the fire trucks through ground. He also had to shoo the fueling truck away and get the ramp personnel away from the main gear for their safety. In addition; the cockpit crew ascertained that the water separator ('sock') was blocked and that the remaining pack was not able to cool the aircraft. Passenger and crew alike were covered in perspiration and visibly overheated. I called Dispatch and said that if the aircraft was not taken out of service that I would refuse it. The aircraft was not taken out of service. The Captain failed to write up the malfunctioning single pack and maintenance signed off the brakes once they cooled without addressing any mechanical issue at all. I wrote up the refusal in the logbook on the basis of the cabin temperature being unsuitable for passenger travel stating that the cabin reached 120 degrees F for the duration of the flight. The aircraft was taken out of service.