high heat recovery efficiency, stable quality, good market reputation,CO2 detector is available 1, air flow 1500 M3/h, 2000 M3/h, high heat recovery efficiency,2, can chose regular AC motor or ECO DC motor3,automatic bypass is available4, preheating is available5,intelligent defrost6,painting is option7,super slim for small space8,varied controller9,CO2 detector is available10,harmful substance ...