DC frequency conversion full heat exchanger DC frequency conversion one-way new fan DC frequency conversion bidirectional flow new fan Special fresh air system for kiosk Air conditioning wind Clean type full heat exchanger (C) Clean type full heat exchanger (x) Clean type full heat exchanger (H) Clean type full heat exchanger Standard full heat exchanger Medium full heat exchanger Full heat exchanger large vertical series Purifying type mute air blower Silent blower fan series Metal duct fan Standard full heat exchanger Wind chassis color steel plate series Clean type bidirection flow fresh air machine Bidirection flow fresh air machine Bidirection flow color steel plate fresh air machine Purifying box Porous Self-balance Branch box Round duct fan Accessories series Accessories series Selection guide Ventilation scheme Engineering case 5 Engineering case 4 Engineering case 3 Engineering case 2 Engineering case 1