In this work, the main features of a nuclear pressurizedthermal hydraulic testing facility named BKTF (BK testing facility) are presented. The facility consists of major systems and components similar to the standard PWR prototype, and it is a volume and pressure scaled model with the total mass of primary coolant in order of hundreds of kilograms. The model is designed to work at normal temperature and pressure less than 160 0C and 10 bars respectively. In this part of research, preliminary results of cold test and hot test are presented. These results show that the system is qualified enough to work under designed pressure and temperature. It is seen that the similarity between temperature and pressure trend lines with these from a real power system during starting up process. In addition, natural circulation was appreciated and compared with forced circulation during the cooling down process and this may help us to have a better vision on passive safety and completely recognize about safety system of nuclear power plant.