Most boilers have a lifespan of 15 to 20 years.

大部分锅炉的使用期限是15到20年。

Make sure that all gas fires and central heating boilers are serviced annually.

确保所有的煤气取暖炉和中央供暖锅炉每年都检修一次。

Water gets heated in such giant boilers.

水在这样的大锅炉中加热。

Hot water boilers (home heating system).

热水锅炉(家用取暖系统)。

Operate steam boilers at two pressure levels?

在两种不同压力水平操作蒸汽锅炉？