hot air stove 1. the hot air boiler use the pure hot air as the medium ,no pullution 2.Higher thermal efficiency hot air stove The hot air stove combustion ... center, circles heat exchanger in the upper and around ,air and flue gas are two-pass ,flow separately in heat ... and turbulent flow principle,thinning laminar flow thickness, make the air and flue gas constantly exchange revolving on the march , ...