Well pump clicking on and off? How to fix short cycling

Signs it's short cycling

• A click every few seconds near the pressure tank while water runs.
• The pressure gauge needle swings up and down quickly.
• Shower pressure pulses strong and weak.
• The pump turns on the moment you open a faucet.

Test 1: the knock test (1 minute)

Knock on the side of the pressure tank from top to bottom. A healthy tank sounds hollow near the top (air) and dull lower down (water). If it sounds dull and solid all the way up, the tank is likely waterlogged.

Test 2: check the air charge (15 minutes)

1. Turn off the pump breaker.It's usually a double breaker labeled “well” or “pump.”
2. Drain the pressure.Open a faucet near the tank and let it run until the gauge reads 0 and the water stops.
3. Find the air valve.It looks like a tire valve, usually on top of the tank under a small plastic cap. Use the small valve, not the large pipe fitting.
4. Read it with a tire gauge.The target is 2 psi below your pump's turn-on pressure. That setting is often printed on the pressure switch or the tank label.

   Switch setting	Tank air should be
   30/50	28 psi
   40/60	38 psi

5. Add air if it's low.Use a bike pump or air compressor until it reaches the target. Close the faucet, turn the breaker back on, and watch a full cycle. The pump should now run longer and rest longer.

Air is fine but it still cycles?

The tank isn't the problem. Other common causes:

• A hidden leak: a running toilet, a dripping outdoor spigot, or a leak in the line from the well.
• A worn pressure switch: its contacts can stick or chatter.
• A failing check valve that lets water drain back down the well.

These need a pump pro. In North Carolina, work on the pump or well must be done by a state-certified well contractor (Level D or higher). Here's how to check.

Already out of water? Start with no water from your well: 5 checks.