The results of bench-scale studies and experimental-commercial tests of ammonium bisulphate applicability for chemical washing of turbine plant heat exchangers with surfaces made of copper alloys were analyzed. The solubility of different iron and copper oxide deposits in ammonium bisulphate solution was investigated in bench-scale experiments. The optimal solution concentration and its circulation time, as well as the time of deposit solving were determined. The conclusion on ammonium bisulphate solution applicability for washing of tube systems made of the L-68 brass was confirmed.