Insufficiently effective operation of inlet tubes in the coolant flow direction during steam condensation in parallel channels with nonuniform heat removal (e.g., in air-cooled steam condensers) has been recognized. It has been revealed by the calculations and the experiments that up to 30% of the inlet tube rows heat-exchange surface area do not participate in heat transfer. The tests conducted at the full-scale condensing units have corroborated this fact. This effect must be accounted for when designing and arranging corresponding cross-flow heat exchangers with cooling condensation. (C) 2012 Published by Elsevier Ltd.