The present work introduces a way of predicting the local heat transfer coefficient in the combustion chamber of a circulating fluidized bed combustor (CFBC) by the fuzzy logic (FL) approach. Fuzzy logic techniques have been successfully applied to calculate the overall heat transfer coefficient for membrane-walls in the combustion chamber of the 670 t/h CFB boiler. The previously obtained heat transfer coefficients values have been used to build up a simple FL model. It has been shown, that the presented fuzzy logic approach give quick and accurate results as an answer to the input data set. The local heat transfer coefficients evaluated using the developed model have been in a good agreement with the desired data. (C) 2015 Elsevier Ltd. All rights reserved.