Heat requirement of greenhouse, calculated according to the principles specified in DIN EN 13032 (formerly DIN 4701) standards, depends on the type of greenhouse, the equipment, climate condition of greenhouse location, and the optimum growth temperature of plants. The heat requirement calculations are usually performed using mean values of daily temperature. However, calculations based on daily average temperature values shows difference from actual values. Determination of optimal heat consumption values in greenhouse were observed when hourly climate values (temperature, solar radiation, and wind) were used. Also, the heat requirement of greenhouses depends on the greenhouse equipments. The type of used heating systems, type of heat curtains used for heat saving and their leaks affect the heat requirement. During the day heat energy was stored and causes temperature increasing in greenhouse. The ISIGER-SERA expert system model calculates the heat requirement in the greenhouse taking into account all these effects mentioned. In this study, it is aimed to test the ISIGER-SERA expert system model in high technology established producer greenhouse located Mediterranean climate zone (Adana). Results showed that only 3% differences were observed between calculated heat energy requirement with ISIGER-SERA expert system model and the actual consumed heat energy in greenhouse.