loss in addition the chamber 130 is substantially isolated from the lower part 132 of the front cabinet compartment 30 which may house the motor 58 and heater assembly 76 by elongate closure plates 134 the closure plates 134 have their outer longitudinal edges fixed to respective cabinet panels and their inner longitudinal edges positioned close to adjacent corresponding walls of the drum the closure members however are sufficiently spaced from the drum to allow for drum rotation and wiper elements or the like may be affixed to such closure members to span the resultant gap to prevent passage of air from the chamber 130 to the lower part 132 of the front compartment 30 at the upper rear of the outer chamber 130 the divider panel 34 is provided with an opening 140 through which air flow is exhausted from such chamber connected to the divider panel 34 at such opening is a vent duct 142 which extends rearwardly and through an opening 144 in the rear panel 22 the vent duct 142 at its rear or exit end may be coupled to an exhaust duct which may lead for example to the outside within the vent duct 142 there is provided a.