If the exhaust system is under a vacuum, the casing must be warmed by gradually introducing the steam, after opening the exhaust valve.

如果排气系统处于真空下，必须在打开排气阀后，逐渐引蒸汽来加热壳体。

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The pressure limit valve is still used to cover the steam nozzle for ensuring the surplus steam to exhaust freely.

汽嘴之上仍用压阀扣上，以保证多余的蒸汽能自由排放。

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Use automatic exhaust valve Spirax Sarco steam system to exclude air and other non-condensable gases, while not leaking steam.

使用斯派莎克的自动排气阀可排除蒸汽系统中的空气及其它不凝性气体，同时不会泄漏蒸汽。

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