The paper examines the problem of temperature distribution in a flat disk-shaped evaporator of a loop heat pipe (LHP) with counter heat and liquid flows. It analyzes the effect of filtration of a cold liquid through a wick on the evaporator temperature field. Calculations have been made for six working fluids, namely, water, methanol, ammonia, acetone, freon R141b and freon R152a. The heat flux supplied to the evaporator varied from 2.83.10(4) to 4.24.10(5)W/m(2). The Peclet number Pe varied in the range from 0 to 3.73. An analysis of the results has shown that at Pe number up to 0.73 the contribution of the convective component to the total heat transfer in the evaporator is insignificant. A criterion K-pe has been suggested for evaluation of the cooling capacity of the liquid in an LHP wick. (C) 2016 Elsevier Ltd. All rights reserved.