PROBLEM TO BE SOLVED: To provide an energy-saving low-cost heating device of an agricultural greenhouse, having a simple structure. SOLUTION: This heating device has an air-conditioning converting area 5 between storage tanks 2 and 3 vertically set in a box body 1. In the air-conditioning converting area 5, a plurality of heat exchange pipes 6 connect the storage tanks 2 and 3 vertically set in the box body 1, and liquid filled in the lower storage tank 3 is heated with a heater 4 built into the lower storage tank 3 to transmit the heat through the heat exchange pipes 6 to the upper storage tank 2. Warm air is discharged from a blast outlet 10 by passing cool air from the outside through the air-conditioning converting area 5 in which warm air is filled by heat radiation action from the heat exchange pipes 6. COPYRIGHT: (C)2008,JPO&INPIT
