ABSTRACT
This study has been undertaken to look at some of the air conditioning systems and select one for designing the air conditioning for the second and the third floors of the Mechanical Engineering Department building, Ahmadu Bello University, Zaria. Many types of air conditioning systems are available; an all-air single zone system is selected and designed for the building. The solar heat gains to the building are calculated using Total Effective Temperature Differential method and the cooling load estimatedrassuming a 12-hour operation of the air conditioning system. The supply air ducts are sized by the static region whereas the return ducts are sized by velocity reduction method. A roof mounted air cooled condensing unit (Westings house ST 020) together with a matching air handling unit (Westinghouse AB 060) are proposed to air condition the building.