General overhaul of hot-water and steam boilers by the following manufacturers TVT-TAM-STADLER, EMO Celje, Ðuro Ðakoviè, Weiss-Toplota, Kohlbach, Loos, Viessmann, Omnical, TPK. Boiler overhauls have several advantages compared to acquiring new ones: * During the overhaul all vital components of boilers are replaced (exhaust pipes, duct walls, combustion chamber... ) making them as new from the aspect of their performance, efficiency and lifetime; * Price of the overhaul does not exceed 50 % of the purchase price of a new boiler; * The services provided carry a three-year warranty; * Boiler overhauls are performed on site which is important for boiler rooms difficult to access. This makes construction as well as installation works unnecessary, there is also no need for lifts and permit application or any other additional administrative procedure.