Fired heaters are generally used to heat the feedstock so that it can be sent to a reactor for processing or to a distillation tower for separation of feedstock into various components. Furnaces, also referred to as heaters, are one of the main pieces of equipment
in a process complex.

1. A furnace may raise the temperature of a gas or hydrocarbon liquid to meet specific processing needs or, in the case of pyrolysis and reformer furnaces, cause a chemical or physical change to the medium.
2. A circular or box-type configuration is primarily used; variations to each design are covered below.
3. In addition, because of the various types of furnaces, this article covers some basics of furnace design and discusses how to approach a piping layout as it relates to maintenance, operation and safety.