The influence of two alcoholic surfactants on the flow patterns of falling film tube bundles is investigated. The flow patterns are measured in a single-stage absorption chiller in the absence of surfactants. The surface tension of H2O/aqueous LiBr solution with different concentrations of 1-octanol and 2-ethylhexanol is measured at low pressure in a saturated atmosphere. Small quantities of surfactants in the aqueous solution do not have an influence on the flow patterns of the condenser and evaporator, while a shift from droplet to jet mode is predicted in the absorber and generator at the typical working condition of an absorption chiller.