Radiant heating panel systems provide high thermal comfort because of low noise level and few required equipments. These panels are installed on walls, floor, and roof in a scale room model. This study aims to investigate the performance of radiant panel heaters. Temperatures inside the room and on its walls were experimentally measured. A numerical model was also employed to study flow pattern inside the room and to predict temperature distribution. The turbulent flow was solved by using RNG k-epsilon turbulent model. Heat transfer by radiation was modeled by using DO radiation model. The results showed that the used numerical technique could accurately predict temperatures distribution in the room. The model was used to study the effect of panel heater locations and sizes on the air flow and air temperature distributions. The heat transfer rates were also calculated numerically as well. It was found that the minimum heat transfer rates were achieved by using the heating panel on the floor, and the scale room model was able to simulate the full-size room within a small percentage error about 20% especially in heater load and the temperature distribution was about less than 1%. (C) 2014 Elsevier B.V. All rights reserved.