In this paper, the authors determine the energy consumption for heating and air conditioning of an administrative building located in the second climatic area, in Romania. The heating and cooling system is provided with fan coils, and the fresh air is supplied by an AHU. The aim is to identify the best solution from 3 proposed heating and cooling systems that can be applied in order to improve the living conditions, namely: boiler with solid fuel (wood) or gas and chiller with mechanical vapor compression (VCM); reversible heat pump; boiler with solid fuel (wood) or gas and absorption chiller type LiBr-H2O driven by solar energy. The goal of the study is to select one of the three solutions which involves minimum investment and exploitation costs.