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The hardware devices used by a gas chromatograph and the separations that occur within its columns are sensitive to temperature change, so a gas chromatograph needs very fine temperature control.

In the first makeshift gas chromatographs the temperature‐controlled enclosure was literally a laboratory oven, and the name stuck; the column compartment of a gas chromatograph is still the column oven.

Early PGCs had a single isothermal oven that housed the sample injection valve, column, and detector; and sometimes the pressure regulator too. The temperature setting was then a compromise that didn't always satisfy the needs of the individual devices. More recent instruments include several temperature‐controlled zones for columns, valves, and detectors, thereby allowing individual temperature settings.

The chromatographic columns are very sensitive to temperature change. A change of column temperature will change the time that a component spends in that column, which might cause an error in analyte detection and measurement. Most columns today reside in a separate column oven often controlled to better than ±0.03 °C.