The New Yorkers who spent a bundle on an outdoor hot tub now admit they rarely use it, "because we can't afford to heat it in winter".

那些花一大笔钱买了一个户外加热浴缸的纽约人现在承认，他们很少使用它，“因为我们在冬天负担不起加热它的费用。”

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The water inside a horizontal vessel is heated by fired burner through burning channel, and the natural gas or crude oil in tube bundle or high pressure coil are heated by hot water.

燃烧器燃烧后通过燃烧道加热水平容器内部的水，然后利用放置在水中的高压盘管或管束加热其中的天然气或原油。

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At Mach 4 or 5, the air flow would become dangerously hot but this heat exchanger - consisting of a dense and closely-guarded bundle of tiny tubes - would chill things down to a manageable temperature in milliseconds.

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