Abstract Contribution deals by optimisation of metal heating from standpoint of scale minimisation. Mathematical model present basic tool for simulation and analysis of heating and scale forming in a continual heating furnace with countercurrent. Mathematical model of heating includes the following processes: fuel combustion process (understoichiometry, overstoichiometry), mass transfer process, conduction, convection and radiation heat transfer process, air suction process into the furnace. Solution of the mathematical model is solution of algebraic and differential equations system. Non iteration method was developed for solution equations system. This method is base of algorithm of simulation model. Mathematical model of scale forming depend on time, temperature and coefficient of air surplus. Simulation model was developed by FORTRAN program language. The models were verificated. Real data and data from model simulation are comparable. Optimal criterion expresses the minimisation of scale. Restrictions for solving of optimal heating have been defined follow: maximal difference between maximum and minimal temperature of charge section on furnace end have to be less as 9°C, the required value of surface temperature have to be 1250°C, air surplus more than 1 for combustion of combustible component in waste gas at temperature under 900°C. The simulation appears that modification of combustion mode decreases of scale forming. In the contribution are described arrangements for reduction of creating scale forming minimisation. Arrangements minimise scale forming from 30 to 50 %, increase quality of heating, and saving energy about 34,5%.