Everywhere, or Just One Tap?
This single distinction saves a great deal of time.
One fixture only
Your well, pump and tank are all fine. It is a plumbing issue at that fixture — almost always a clogged aerator (the screen in the end of the spout), a partially closed shut-off valve underneath, or a failing cartridge inside the tap.
Unscrew the aerator, rinse out the grit, put it back. On well water with any sediment this resolves it more often than anything else, and it costs nothing.
Everywhere in the house
Now it is the system, and the list below applies. Work down it in order — the first two are free to check and between them they account for a large share of cases.
One thing to note as you go: when the pressure is poor matters as much as how poor it is.
Causes, Most Likely First
| Cause | How to tell | Fix |
|---|---|---|
| Clogged sediment filter | Gradual decline; the cartridge looks dirty | $10–$40 — check this first |
| Partially closed valve | Started after other plumbing work | Free |
| Switch set low | Consistent; has never been better | $150–$400 |
| Pressure tank losing charge | Pump short-cycles rapidly | $400–$1,200 |
| Mineral buildup in old pipe | Worse the further from the tank; old galvanised plumbing | Plumbing replacement |
| Leak in the system | Pump runs when nothing is in use | Locate and repair |
| Declining well yield | Fine at first, fades after a few minutes | Storage / fracking / deepening |
That last row is the one that matters most to identify correctly. If your pressure is good for the first few minutes of a shower and then fades away, stop looking at the plumbing. That is the well being drawn down faster than it refills — a yield problem — and the instinctive fix of a bigger pump makes it actively worse by emptying the well faster.
What Pressure Should It Actually Be?
Most systems run 40/60 — the pump starts at 40 psi and stops at 60. 30/50 is also standard and common on older systems. If your house feels persistently low and you find it set at 30/50, moving to 40/60 is sometimes a genuine and inexpensive improvement.
It is not always appropriate, though, and this is worth saying plainly: an older well, an ageing pump, or old plumbing that has been happily living at lower pressure can all argue against turning it up. More pressure asks more of every component. We would rather look at the system and tell you honestly whether it will take it than adjust a switch and leave.
- Check the sediment filter first — it is free and it is the commonest answer
- Confirm the main valve is fully open
- Note the cut-in and cut-out pressures from the gauge
- Note whether pressure is poor everywhere or only at some fixtures
- Note whether it is constant or fades with use
- Listen to the pump while a tap runs — steady, or rapid cycling?
Questions
Will a bigger pump fix low pressure?
Almost never, and on a low-yield well it makes things worse. Pressure is set by the pressure switch, not by pump size, and a larger pump on a well that cannot keep up simply empties it faster and then runs dry. If anyone offers a bigger pump as the answer to low pressure without diagnosing the cause, get a second opinion.
Could it be the well running low?
If pressure fades during use and recovers after a rest, yes — that is the signature of a yield problem. If it is consistently low from the first second and stays there, the well is probably fine and the cause is somewhere between the tank and the tap.
Does a water treatment system reduce pressure?
It can, particularly if the filters or media need servicing. Softeners, sediment filters and iron filters all introduce some resistance by design, and a neglected one introduces a great deal. If you have treatment equipment and pressure has been declining gradually, service that before assuming anything about the well.
Why is pressure worse upstairs?
Partly just physics — every foot of height costs roughly half a psi — so an upstairs bathroom always reads lower than the basement. It becomes a problem when the baseline is already marginal, which is when raising the switch settings, if the system will take it, genuinely helps.