The decrease of energy sources, the increase of energy need and energy costs, competitive conditions in industry and environmental sensitivity require the effective usage of energy sources. In this study, optimum combustion study by using thermal camera and pyrometer in the correct heat furnace of an industry plant for the effective usage of energy in industry. For this reason, in tempering furnace of a milling roll workshop, in order to control the efficiency of tempering, detect the flame length and color and control the homogeneous tempering, 4 thermal cameras and 4 pyrometers have been assembled to the appropriate locations of the furnace. In the study, the tempering furnace has been observed and the results of observations have been evaluated. The contribution of the changes made to the production has been calculated by the information obtained from thermal camera and pyrometer and has been examined with the date of reimbursement. Possible spare part and production saving has been established as 364,460 $ annually and back-payment time as 3 months. Accident risk that is caused by the hot air and sometimes occurs during the controls has also been reduced so that the workers have been forced to work more safely according to WHS (workers' health and security).