警报器，进水阀或泵启动装置开关在燃烧器关闭燃烧之前启动。

Alarm, feed valve or pump starter switch actuates just before the burner switch cuts the firing.

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警报器，进水阀或泵启动装置开关在燃烧器关闭燃烧之前启动。

Alarm, feed valve or pump starter switch actuates just before the burner switch cuts the firing.

youdao