Watts air scoops have heavy cast iron construction.They have tappings for the installation of an expansion tank and air vent. 美国瓦茨导气罩具有重型铸铁结构，并都配置用于安装一个膨胀罐和排气阀的连接端口。
At the same time air is sucked into the inlet to replace the exhausted air. 同时，外面空气由进气口吸入代替被排出的空气。
Are air conditioning intakes which may permit the entry of cargo vapours closed? 有可能吸入货物蒸汽的空调系统进气口是否已关闭？
