To prevent dew concentration on a cross flow fan or the like by completely shielding an insertion hole for insertion of the shaft of a motor from air.

A cylindrical shaft cover 15 is mounted on the outer circumference of a shaft 11b of a motor 11 and one side of the shaft cover 15 is inserted and mounted into the outer circumference of a vibrationproof rubber 12 provided on a bearing part 11a of the motor 11 while the other side thereof is fitted into an insertion hole 14 provided at a contact part with a base partition plate 2a to separate an air path of air passing through the heat exchanger and a motor mounting space and a casing partition plate 13c. This completely shields the insertion hole 14 to block outside air from advancing to the air path which lets the air heat exchanged pass thereby preventing dew concentration on a cross flow fan 10 or the like.