The invention relates to a method for operating a washing machine (28) having a heating unit (11), wherein the heating unit comprises a carrier (13) and at least one planar heating element (17, 18) disposed thereon. At least one first heating element (17) is attached to the carrier (13) in a planar manner, wherein the carrier has a recess extending in the longitudinal direction in the center region. The washing machine (28) has a washing machine barrel (30) and a drum (29) therein, wherein the heating unit (11) is displaced at the bottom in the washing machine barrel (30) outside of the drum (29). A heating element is provided on the outside of the carrier in the region of the recess in the region along an apex, or along an apex of the recess, wherein only said heating element (17) is operated in the region of the recess for creating steam in the washing machine (28).