Furnace (central heating)

Device used for heating buildings

A furnace is an appliance and fixture that is used to generate hot air for all or part of a building. Furnaces are mostly used as a major component of a central heating system. The most common fuel source for modern furnaces in North America and much of Europe is natural gas; other common fuel sources include LPG (liquefied petroleum gas), fuel oil, wood and in rare cases coal.

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