PURPOSE: To achieve latent heat exchange of high efficiency by a method wherein, in a disk-shaped rotary type latent heat exchanger which has a large number of small holes passing through the opposite end surfaces thereof and which enables latent heat exchange by the use of absorbent materials in the small holes as a medium, the size of the holes on the end surface part on the side of air inlet is made larger than that of the holes of the other part.

CONSTITUTION: A rotary type latent heat exchanger 1 consists of a first porous body 2 having a predetermined diameter, second porous bodies 3, 3 which have the same diameter as the body 2 and which are closely connected to the opposite ends of the body 2 respectively, and an axial rod 4 which is disposed through the center of the body 2 and the bodies 3, 3. The first body 2 is formed in such a manner that an absorbent material in the form of a plane is superposed on a corrugated material provided by forming the absorbent material into a corrugated form to form a one-side corrugated board-like belt-shaped plate, which plate is wound into a helical form. The planar material and corrugated material are impregnated with liquid absorbent material. The second bodies 3, 3 having holes larger than the holes of the first body 2 are disposed on the opposite sides of the first body 2.