A well-insulated 4m x 4m x 5m room initially at 10oC is heated by a radiator of a steam system. The radiator has a volume of 15 L and is filled with superheated vapor at 200 kPa and 200oC. At this moment with both the inlet and exit valves to the radiator are closed. A 120-W fan is used to distribute the air in the room. The pressure of the steam is observed to drop to 100 kPa after 30 minutes as a result of the heat transfer to the room. Assuming constant specific heats for the air at room temperature, determine the average temperature of the air in 30 min. Assume the air pressure in the room is constant at 100 kPa