The jacket of the vessel was connected to a circulating hot water source.

容器的夹套与循环热水源相连。

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A group of horizontal secondary heating pipes communicating with the double-layer water jacket can be arranged in the flue of the hot-water boiler.

本实用新型的烟道中可以设置一组与双层水套相通的横置二次加热管。

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Assistance could be in the form of installation of draught proofing, loft insulation, hot water cylinder jacket or more effective heating controls and training on how best to use them.

BBC: NEWS | UK | Northern Ireland | Pilot scheme tackles fuel poverty