A changeover manifold is a system of valves and pressure regulators that delivers gas to a process without gas flow interruption. Most changeovers consist of a regulator scheme that reduces the pressure in two stages to achieve a constant outlet pressure.

Users should be aware that there are systems offered that do not provide two stages of pressure reduction and that the resultant outlet pressure will fluctuate considerably as the system operates, thus requiring the addition of a line regulator down stream from the changeover to provide a consistent pressure to the process.