Pump Cycles On and Off Repeatedly

Symptoms

• Pump turns on, builds pressure, shuts off, then turns on again within seconds
• Rapid clicking from the pressure switch
• Fluctuating water pressure

Diagnosis

The pressure tank has lost its air charge (waterlogged), so there's no air cushion to maintain pressure. The pressure drops immediately when any water is used, triggering the pump again.

Step-by-Step Repair

1. 1

   Turn off the pump. Check the pressure tank's air charge by pressing the Schrader valve (like a tire valve) on top of the tank.

2. 2

   If water comes out of the Schrader valve, the tank bladder has ruptured. Replace the tank.

3. 3

   If air comes out, check the air pressure with a tire gauge. It should be 2 PSI below the pump's cut-in pressure (typically 28 PSI for a 30/50 switch).

   Only check air pressure with the pump off and the tank drained.
4. 4

   Use a bicycle pump or compressor to add air if the pressure is low.

5. 5

   If the tank is fine, check for a small leak anywhere in the system. Even a dripping sprinkler head will cause cycling.

6. 6

   Also check the pressure switch contacts — pitted or corroded contacts cause erratic switching. Clean or replace the switch.