Heat recovery defrosting fresh air device and method

The invention discloses a heat recovery defrosting fresh air device and method, and relates to the technical field of heat energy conversion and transmission. In order to solve the technical problem that in the prior art, a defrosting fresh air system which can adapt to the northern winter cold environment and is low in cost is urgently needed at present, according to the scheme, the heat recovery defrosting fresh air device comprises a centrifugal fan, and the centrifugal fan comprises an indoor suction fan and an outdoor suction fan; one end of the heat exchanger is connected with the centrifugal fan; the through hole plate comprises a first through hole, a second through hole, a third through hole and a fourth through hole. The first through hole and the third through hole are connected with an indoor suction fan, and the second through hole and the fourth through hole are connected with an outdoor suction fan. The first through hole and the second through hole are connected with a first channel, and the t