We have determined the excess molar enthalpies H-m(E) of binary mixtures containing an alpha,omega-dichloroalkane (from 1,3-dichloropropane to 1,6-dichlorohexane) and a I-alkanol (1-pentanol, or 1-hexanol) using a Calvet microcalorimeter at the temperature T = 298.15 K and normal atmospheric pressure. All mixtures exhibit endothermic behaviour for the whole composition range. The experimental values were compared with values calculated from three versions of a UNIFAC group-contribution formalism. The experimental and calculated results are discussed in terms of molecular interactions and the proximity effect.