Well Pump Making Noise — What Each Sound Means

Well Pump Noise Diagnostic Guide

🔴 Rapid Clicking (Every Few Seconds)

Cause: Pressure switch short cycling — the pump is turning on and off every few seconds.

Source: The clicking sound comes from the pressure switch contacts opening and closing rapidly.

Fix: Almost always a waterlogged pressure tank. Test the Schrader valve — water means replace the tank. If air comes out, check pre-charge pressure (should be 2 PSI below cut-in).

🔴 Humming Without Starting

Cause: Motor receiving power but unable to start spinning (locked rotor).

Fix: Turn pump OFF immediately — check capacitor first. A domed/bulging capacitor = replace it. If capacitor is fine, check for seized impeller or low voltage.

🟡 Grinding or Rattling

Cause: Sand or sediment being pumped through impeller, or worn bearings.

Fix: Check water for sediment. If sand is present, pump may be set too close to well bottom. Worn bearings indicate pump is near end of life.

🟡 Banging Pipes When Pump Starts

Cause: Water hammer — pressure surge when pump starts into empty pipes.

Fix: Almost always a waterlogged pressure tank with no air cushion. Replace or recharge the tank. A water hammer arrestor on the supply line also helps.

🟡 Squealing or Screeching

Cause: Worn pump bearings or cavitation (pump drawing air).

Fix: Bearing wear requires pump replacement. Cavitation may mean low well water level or air leak in suction pipe.

🟢 Normal Sounds

A healthy above-ground jet pump produces a steady motor hum during operation. A healthy submersible pump is nearly silent at the surface — you may hear water flowing but not the motor. Pressure switch clicks once at cut-in and once at cut-off are normal.