The application of Adomian Decomposition Method (ADM) is extended to investigate all phenomenon of heat transfer, i.e., conduction, convection and radiation occurring in the hot furnace. In this work, a square furnace is considered for the thermal analysis with temperature dependent properties. There are two layers of different material in the furnace out of which one is having internal heat generation and the other one would act as an insulator. It is found from the present study that the results obtained from ADM are in good agreement with the results of the differential transformation method available in the literature. The thermal properties of the selected system, i.e., thermal conductivity of both materials, heat transfer coefficient (inside and outside of furnace) and emissivity are considered as non-linear temperature dependent. Moreover the temperature dependent internal heat generations are also incorporated into the modeling of furnace. ADM being the semi-analytical technique for solving non-linear equations, the required temperature distribution has been obtained. In the forward problem, the temperature distributions and efficiency are investigated for various influencing parameters.