Pump Operations
Hydrant Changeover
Hydrant changeover is the transition from running on tank water to running on a hydrant supply without interrupting the attack line. Done smoothly, the line never notices the source has changed underneath it.
The goal is continuity: bring the hydrant water to the intake, open it, and back the tank out so the line stays charged the whole time. As flow comes on, the operator watches the hydrant's static pressure become a residual reading under load.
Rushing the changeover risks losing the line or air-binding the pump. The skill is sequencing the valves so the pump always has a source — tank water covering the gap until the hydrant is carrying the load.
Where this shows up
Scenario
Hydrant TransitionCalculator
Hydrant Available Water