Ventilation system with thermal energy recovery

Claim 1

A forced air, non-recirculating ventilation system for an enclosure in which a thermal energy gradient relative to outside ambient air temperature has been produced by the expenditure of energy, said system comprising: first means defining a distribution duct from an outside air source to said enclosure; first air-flow-forcing means operatively associated with said first duct for producing a substantially continuous, unidirectional flow of substantially exclusively outside air to said enclosure; second means defining an exhaust duct from said enclosure to the outside air source; second air-flow-forcing means operatively associated with said second duct for producing a substantially continuous, unidirectional flow of inside air from said enclosure substantially completely to the outside; first and second matrices of thermal energy absorbing material, each being characterized by a high surface area to volume ratio and low hydraulic resistance; housing means for said matrices and arranged for air flow therethrough, to and from outside air; and valve means connecting said housing means to said first and second duct means for alternately reversely hydraulically connecting the duct means to respective matrices thereby to draw outside air into said enclosure to ventilate same through one matrix while complementally exhausting inside air from said enclosure through the other matrix.