A simple analysis of the pressure drop-flow relationship in a single tube laminar flow cooler shows a maximum and minimum in the resulting curve. Operation in the region between this maximum and minimum pressure drop can result in a maldistributed flow in multitubular coolers. Equations and a chart are developed to easily calculate the maximum part of the curve. The criteria to avoid maldistribution in multitubular coolers is operate with a pressure drop greater than this maximum point.