. Air heat exchangers of the side-evaporating type based on the Maisotsenko cycle have a higher transformation coefficient, so it is advisable to use them for cooling livestock premises. However, one of the tasks of increasing the efficiency of such heat exchangers is to optimize its parameters by reducing pneumatic losses. Therefore, the aim of the research is to determine the pneumatic losses of the heat-evaporating type heat exchanger and to establish the regularity of the change of pressure and power losses required for pumping air through it from its design and technological parameters. As a result of analytical researches of pressure losses of the air heat exchanger of side-evaporating type dependences of losses of pressure and power on quantity of channels, the area of section of channels, average speed of air in channels provided their equality and their form (square, equilateral triangle, circle). It is established that the most effective form of channels in the aspect of pneumatic losses (reduction of pressure losses by 23%) have channels in the form of an equilateral triangle.