The paper is devoted to the analysis of thermoelectric cooling phenomena in semiconductors containing potential barriers (p-n -junction). The formulation of an adequate self-consistent theoretical model describing the effect is presented. The role of the recombination rate as a new source of heat in linear approximation of the electric current was discussed, leading to a reformulation of the heat balance equations. The importance of redistribution of nonequilibrium charge carriers, which has been ignored in most publications on this subject, is also shown. The conventional theory of thermoelectric cooling, not taking into account the influence of the nonequilibrium charge carriers, is shown to be inadequate. Besides, when the recombination rate decreases, cooling changes to heating. © 2009 American Institute of Physics.