Vertical pressure tank connected to a water pump outdoors

Well pressure switch chattering or clicking rapidly

Chatter happens when the switch sees pressure bouncing around its set point. The usual causes are a plugged sensing port or nipple, a waterlogged or low-precharge tank, a switch mounted far from the tank, worn contacts or a differential set too narrow. Chatter burns contacts fast and stresses the motor, so fix it the same day.

Cross-checked ~45 min moderateBrands: All

Before you start

240 V at the switch: turn off and lock out the breaker, verify dead before removing the cover
Relieve water pressure before removing the switch or its fitting

Diagnostic steps

Unlock all 8 steps with expected values

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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