PURPOSE: To obtain a total heat exchanger, having no corrosive property and high total heat exchanging efficiency, by a method wherein the total heat exchanger is provided with a partitioning plate, which exchanges temperature and humidity between primary air stream and secondary air stream, while the partitioning plate is constituted so that the surface of a water absorbing polymerized resin is coated by a fine porous polymerized film.

CONSTITUTION: A partitioning plate 2 is constituted of a water absorbing polymerized resin 4 and fine porous polymerized films 5, 6, sandwiching the polymerized resin 4. In this constitution, primary air stream A to be discharged is sent to the primary air stream passage 7 of a total heat exchanger 1 by a fan. On the other hand, a secondary air stream B, which is supplied, is sent into the secondary air stream flow passage 8 of the total heat exchanger 1. The temperature (heat) of the primary air stream A to be discharged is shifted to the secondary air stream B by the fine porous polymerized films 5, 6 and the water absorbing polymerized resin 4, which are constituting the partitioning plate 2. On the other hand, the vapor of water in the primary air stream A to be discharged is accumulated into the water absorbing polymerized resin 4 through the openings 9 of the fine porous polymerized film 5 and is dissipated into the secondary air stream B to be supplied through the openings 10 of the fine porous polymerized film 6, different from the fine porous polymerized film 5.