Pressure centrifugal fan _ pressure centrifugal fan Company Name: Henan Hongji Blower Co., Ltd. Company website: www.guolufengji188.com company sales hotline: 0394-7892627 15518086290 QQ: 445528270 natural wind installation in the same direction. Fan is the use of negative pressure ventilation principle, it is out of ventilation, such as when installing the wind is different, and natural wind offset weakening its exhaust effect. When the temperature is high and the case of large wind, the effect may be counterproductive. The fan is mounted at the highest possible point. This can effectively indoor uppermost gas, heat pumped, efficiency will increase.