Vent discharges C02 gas to atmosphere in the event of fouling or malfunction of check No. 2 thereby safeguarding the potable water system from CO2 gas contamination.

• 万一第二止回阀被污染或出现故障，排气口将C02气体排放到大气中，从而保护饮用水不会受到C02气体的污染。