Why the Tank Matters More Than It Looks
A pressure tank is not storage in any meaningful sense. It is a cushion. Inside is a bladder with an air charge on one side and water on the other. Water compresses the air; the air pushes water back out when you open a tap. That cushion is what lets you draw a glass of water without the pump starting at all.
When the charge is lost, the cushion disappears. Now every draw starts the pump, which runs for a couple of seconds and stops. That is short-cycling.
Motors are worn out by starting, not by running. A short-cycling system can put a pump through more starts in a month than a healthy one sees in a year.
It is the single most common avoidable cause of premature pump failure in this region, and it is quiet. Nothing dramatic happens. The water still works. People live with it for months without knowing, and then pay for a pump.
The ten-second test: run a tap and listen to the pump. Steady run, then stop — healthy. Rapid on-off-on-off — short-cycling, and the pump is paying for it right now. A second check: tap the side of the tank from top to bottom. Hollow above and solid below is healthy; solid all the way up means it is waterlogged.
A Different Family of Problems
Low pressure with a pump that is cycling normally usually points somewhere other than the well, which is good news — the fixes range from free to modest.
| Cause | Tell | Typical fix |
|---|---|---|
| Clogged sediment filter | Gradual decline; filter looks dirty | Cartridge, $10–$40. Check this first |
| Partially closed valve | Appeared after other plumbing work | Free |
| Switch set low | Consistent, never been better | Adjustment or new switch, $150–$400 |
| Pressure tank losing charge | Pump short-cycling | Tank, $400–$1,200 |
| Mineral buildup in old pipe | Worse at fixtures furthest from the tank | Plumbing replacement |
| Leak in the system | Pump runs when nothing is being used | Locate and repair |
| Declining well yield | Fine at first, fades after a few minutes | Storage, fracking or deepening |
That last row is the one that matters most to get right, because it is the one where the instinctive fix — a bigger pump — makes things actively worse. If pressure is good for the first few minutes and then fades, stop looking at the plumbing and look at the well.
- Short-cycling diagnosed before it takes the pump with it
- Tank air charge checked and set properly
- Pressure switch settings matched to the tank
- Low pressure traced to its actual cause
- Tank checked as standard whenever a pump is replaced
- Honest advice when the real problem is yield
Tank & Pressure Questions
How do I know if my pressure tank has failed?
Run a tap and listen to the pump. Healthy: runs steadily, then stops. Failed tank: kicks on and off every few seconds. Also tap the tank from top to bottom — hollow above and solid below is right; solid all the way up means it is waterlogged and has lost its charge entirely.
How long do pressure tanks last?
Commonly ten to fifteen years, varying with water quality and how hard the system works. The important point is that they fail gradually rather than dramatically, so nothing tells you except the cycling behaviour. That is why so many are only found after they have already cost a pump.
Can I just recharge the tank instead of replacing it?
Sometimes, and it is worth checking before assuming replacement. A tank that has simply lost air pressure over time can be recharged if the bladder is intact. A tank whose bladder has failed cannot — it will hold the charge for a short time and lose it again. Establishing which you have takes a few minutes and it is the first thing we do.
What pressure should my system run at?
Commonly 40/60 — the pump starts at 40 psi and stops at 60 — though 30/50 is also standard, particularly on older systems. If your house feels low on pressure and it is set at 30/50, moving to 40/60 is sometimes a genuine improvement. It is not always appropriate, though: an older well, an older pump or fragile plumbing can all argue against it.
My pressure is fine then fades after a few minutes. Is that the tank?
No, and this is the important distinction on this page. That pattern is a yield problem — the well is being drawn down faster than it refills. A tank cannot cause it and a bigger pump would make it worse. See well ran dry for the actual options.