Thermoluminescence (TL) of minerals contained in bricks can contribute to an objective dating of brick walls analogously to the more often used dating of ceramics. The design concept of our "home-made" reader has been influenced by the necessity of automation. The instrument automatically measures, stores and evaluates the data of up to 60 samples. The paper summarises an experience with testing the new machine and the technique of TL sample preparation with the aim of fulfilment the demands of reliability and other operational characteristics.