In this paper, Multi-Objective Optimization (MOO) of the cooling and heating systems at the faculty of engineering of Arak University is investigated to increase the comfort and reduce the cost of energy. For this purpose, the faculty building is modeled and the comfort and cost of the faculty are calculated. In the next step, a database of 2,000 faculties with different design variables will be created and analyzed. Buildings with the best objective functions are selected and presented in a Pareto front. Design variables are the 11 geometrical and non-geometrical factors affecting the comfort and cost of the faculty. The objective functions are comfort, cost and energy consumption. The results indicate that both absorption and compression systems have the ability to achieve acceptable levels of comfort, but the amount of energy consumed in the absorption chiller is higher than the energy consumption of the compression system, which requires the necessity of using absorption systems in conditions of waste heat. Also, the results indicate that the absorption system, despite the higher energy consumption than the compression system, has lower energy consumption costs due to the difference between electricity and gas tariffs in Iran country and should be corrected.
