How often should you check a well pressure tank?
Updated July 2026
Check a well pressure tank's air charge once a year, and set it to 2 psi below the pump's cut-in pressure with the tank fully drained of water. That precharge is what lets the tank hold a cushion of air, so the pump runs in long, healthy cycles instead of flicking on and off every few seconds. A drained tank on a 30/50 switch, for example, should read about 28 psi at the air valve up top. Get this number wrong and you shorten the pump's life dramatically.
What changes the interval
| Your situation | Interval | Why |
|---|---|---|
| 30/50 pressure switch | Precharge ~28 psi | Two below the 30 psi cut-in, checked with the tank empty |
| 40/60 pressure switch | Precharge ~38 psi | Same rule: 2 psi under the cut-in setting |
| Pump kicks on rapidly (short-cycling) | Check the charge now | A waterlogged tank is the classic cause; the bladder may be shot |
| Tank feels heavy or water spits at taps | Inspect the bladder | Air has bled off or the bladder ruptured, letting water fill the air side |
| New tank or new pump install | Set precharge to match | The factory charge rarely matches your switch out of the box |
The cost of skipping it
What skipping it costs: when the air charge bleeds off, the tank waterlogs and loses its cushion, so the pump cycles on and off every few seconds under any draw. That rapid short-cycling burns out the pump motor and pressure switch fast; a submersible well pump replacement runs $800 to $2,500+ once you factor in pulling it from the well. A bladder tank itself is $150 to $500. A five-minute annual charge check is what stands between the two. If you suspect the bladder, see why a pressure tank waterlogs.
How to do it (15 minutes · DIY with a tire gauge)
- Cut power to the well pump at the breaker so it cannot refill the tank.
- Open the nearest faucet and drain the tank completely until water stops.
- Find the air valve (a Schrader, like a tire valve) under the cap on top of the tank.
- Press a tire gauge on it and read the pressure; a little water spitting out means a failed bladder.
- Add air with a bicycle or 12V pump, or bleed some off, until it sits 2 psi below your cut-in setting.
- Recap the valve, restore power, and let the tank refill; confirm the pump cycles slowly under a running tap.
Knowing the interval is the easy half. OnOtto reminds you at the right interval, and it won't let you snooze it into next year. Tasks persist until they're done, and completing pressure tank checks schedules the next one automatically.
Put this on autopilot, free for 30 daysFrequently asked questions
How do I know what my cut-in pressure is?
It is printed on the pressure switch or set by whoever installed the system, and it comes as a pair like 30/50 or 40/60. The lower number is the cut-in, where the pump starts; the higher is the cut-out, where it stops. Watch the gauge near the tank through one full cycle and note the pressure where the pump kicks on. Your tank precharge should be 2 psi below that cut-in number, measured with the tank drained. If you change the switch settings, reset the precharge to match.
What does a waterlogged pressure tank feel like?
The tell is the pump: it short-cycles, snapping on and off rapidly whenever you run water, sometimes several times a minute. You may also feel the tank is unusually heavy when you rock it, get sputtering air at the faucets, or hear the pump running far more than it used to. All point to a lost air cushion, either a bled-down charge you can top up or a ruptured bladder that means a new tank. Either way, act quickly before the constant cycling kills the pump.
How long should a well pressure tank last?
A bladder or diaphragm pressure tank typically lasts 5 to 10 years, sometimes 15 with a correct precharge and stable water chemistry. The bladder is the wear part: once it ruptures, the tank waterlogs no matter how much air you add, and replacement is the fix. Checking and correcting the air charge every year is the best way to reach the long end of that range, because a proper cushion keeps the pump from hammering the system. See how long a well pressure tank lasts.