Problems encountered in use of pulverized coal, in particular, have practical implications related to coal blending and up-grading of imported coals. Practically, significant problems are recognized in such aspects as control of the combustion process, fireside corrosion, ash and pollution. The methodology of predicting problems using pilot scale facility is less expensive, requires less coal and less time to execute, compared to the use of full scale facility. In this study, evaluation of Indonesian Roto coal was performed in a pilot scale coal combustion test facility. Burnout ratio of coal was higher then 98%, and increase of swirl number and preheat temperature of air made flame stabilize. NOx concentration in flue gas was lower in the range 0.5-0.9 of swirl number. Concentrations of oxygen and carbon dioxide in flue gas were constant in spite of variation of swirl number in this work.