Vertical pressure tank connected to a water pump outdoors

Field pattern: well pump short cycling (tank air charge before the pump or switch)

Rapid cycling is usually the pressure tank, not the pump: lost air charge or a failed bladder leaves no drawdown, so the pump hits cut-out almost immediately. The wrong turn is pulling the pump or swapping the pressure switch first; checking the tank's air pre-charge with the system drained takes minutes.

Cross-checked ~45 min moderateBrands: Amtrol, Flexcon, All

Before you start

Turn off the pump breaker before draining or working on the tank or pressure switch
The pressure switch carries line voltage (often 240 V); verify zero voltage before opening the cover and test live only with insulated probes
Do not over-pressurize the tank; follow the tank label's maximum
Pulling a submersible pump or working inside the well is a well contractor's job

Diagnostic steps

Unlock all 7 steps with expected values

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