Abstract: A space heating apparatus comprising a main enclosure having a front and a rear wall, side walls and a top and bottom wall. An air inlet opening is provided in the front wall with a filter removably secured therein. An impeller fan is mounted within the enclosure adjacent the opening for drawing outside air into the enclosure through the filter and convecting it through predetermined paths in the enclosure and out of the enclosure through vent openings provided therein. Heating elements are secured in the enclosure between the fan and the rear wall for heating the air. A water reservoir having a heater therein is provided in the enclosure. The water in the reservoir is heated to the boiling point whereby water vapor is mixed with the air convected through the predetermined paths. Control means are further provided for regulating the operation time cycle of the fan, heating elements and heater.