主通气立管
/ˈmeɪn ˈsɜːkɪt ˈvɛnt/
n
English: main circuit vent · 主通气立管
English · main circuit ventEspañol · toma de aire principalFrançais · colonne de ventilation principale
释义：Vertical pipe vented directly outdoors that allows air to circulate throughout the draining circuit; it also vents sewer gas.