moi nguoi cho minh hoi phong nha minh rong 30m2 neu lap cai 9000btu thi nho wa. vay minh lap 2 cai 9000 co duoc khong va so sanh giua lap 2 cai 9000 va lap 1 cai 18000 thi lap loai nao tot hon. vi minh dang co 1 cai 9000 roi bay gjo chuyen phong rong hon nhung bo di thi phi nen mun moi nguoi tu van giup