fresh air ventilator---celling series(1) Installed in celling, save room space, no influence on decoration effect. fresh air ventilator---celling series(1)fresh air ventilator description fresh air ventilator description 1,structural style: B-plate, Z-rotator, R-heat tube2,Performance : Q- total heat exchanger, X-sensible heat exchanger3,Installation form: D-celling, L-vertical, G- Wall Hanging4, ...