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A C-55 Water Conditioning license authorizes installing water-conditioning equipment and the pipe and fittings needed to connect it to a building’s water supply — a deliberately narrow scope under 16 CCR §832.55. Read the complete C-55 exam guide for requirements and exam structure.
CSLB’s own C-55 exam study guide frames the license around bypass piping — routing only the pipe and fittings needed to connect conditioning equipment and exclude specific fixtures, like outside hose bibbs, from conditioned water. A C-36 Plumbing contractor’s scope is far broader and covers the general water distribution system; C-10 Electrical overlaps only on the power connection that runs the conditioning unit.