Check your pressure tank and pump settings first

Most household water pressure problems start with the pressure tank or the pump's cut-in and cut-out settings, not with the pump itself. A pressure tank stores water under pressure so the pump does not run constantly; when the tank loses its air charge, pressure drops even though the pump works fine. Before you buy a new pump, check whether your tank still holds air and whether your pump's pressure switch is set correctly.

The pressure switch tells the pump when to turn on and off. If it is set too low, your system will never build enough pressure. Most residential pumps are set to cut in around 30 pounds per square inch (psi) and cut out around 50 psi — meaning the pump stops when pressure reaches 50 psi. If your pressure is consistently below what you need, the cut-out setting may be too low, or the tank may have lost its air charge.

Key Takeaways

  • A waterlogged pressure tank — one that has lost its air charge — is the most common cause of low pressure and can usually be fixed by draining and recharging it.
  • The pump's pressure switch has two settings: cut-in (when the pump starts) and cut-out (when it stops); raising the cut-out setting increases maximum pressure, but most residential systems are already near their safe limit.
  • Increasing pump speed or impeller size requires opening the pump housing and is a job for a licensed well pump technician, not a homeowner repair.
  • If pressure is low only at certain fixtures or times of day, the problem is usually a clogged intake line, sediment in the tank, or a failing check valve — not the pump itself.

Drain and recharge your pressure tank

A pressure tank that has gone waterlogged will not hold pressure no matter how hard the pump works. Over time, the rubber bladder or diaphragm inside the tank can fail, allowing water to fill the entire tank and squeeze out the air. You can test this by tapping the tank with a wrench — a hollow sound means air is still inside, while a solid thud means it is full of water.

To recharge the tank, turn off the pump and open a faucet to drain all pressure from the system. Then drain the tank completely using the drain valve at the bottom. Once empty, use an air compressor to add air back into the tank through the air valve (usually a tire-type valve at the top). The air pressure should be set about 2 psi below your pump's cut-in pressure — so if the pump cuts in at 30 psi, charge the tank to 28 psi. Turn the pump back on and check your pressure at a faucet.

Adjust the pressure switch settings

If recharging the tank does not solve the problem, the pressure switch itself may need adjustment. The switch has two nuts or screws: one controls the cut-in pressure (when the pump starts), and one controls the cut-out pressure (when it stops). The difference between them is called the differential — typically 20 psi in a residential system.

To raise your maximum pressure, you adjust the cut-out setting upward. Loosen the larger nut on top of the switch and turn it clockwise to increase pressure. Make small adjustments — a quarter turn at a time — and test the pressure at a faucet after each change. Most residential systems should not exceed 60 psi; going higher can damage fixtures, appliances, and pipes. If you are already near 60 psi and still need more pressure, the problem is not the switch — it is the pump itself or something blocking water flow.

Look for blockages in intake lines and check valves

Low pressure that appears suddenly, or pressure that is low only at certain times or fixtures, often points to a blockage rather than a pump problem. Sediment, mineral buildup, or debris can clog the intake line from your well or water source, or they can jam the check valve — a one-way valve that prevents water from flowing backward into the well.

If pressure is low everywhere in the house, the intake line or check valve is the likely culprit. You can test the check valve by turning off the pump and opening a faucet; if water drains out slowly or not at all, the valve is stuck. A licensed pump technician can clean or replace a check valve and flush the intake line. If pressure is low only at one or two fixtures, the problem is usually a clogged aerator or screen at that fixture, not the pump — unscrew the aerator and rinse it under running water.

Increase pump speed or impeller size — when to call a technician

If your pressure tank is charged, the switch is set correctly, and there are no blockages, the pump itself may not be powerful enough for your needs. A pump's flow and pressure are determined by its motor speed (measured in revolutions per minute, or rpm) and the size of its impeller — the spinning part that moves water. Increasing either one increases pressure.

However, changing these requires opening the pump housing and is not a homeowner job. A licensed well pump technician can adjust the motor speed by changing the pulley size (on belt-driven pumps) or by replacing the impeller with a larger one. Both changes cost less than replacing the entire pump, but they require the right tools and knowledge of your specific pump model. If your pump is more than 10 to 15 years old and pressure has been dropping gradually, replacement may be more cost-effective than repair.

Install a booster pump for low-pressure situations

If your main pump cannot deliver enough pressure — or if pressure is adequate most of the time but drops during peak use — a booster pump can be added to the system. A booster pump sits downstream of your main pump and adds extra pressure where you need it most, such as to an upstairs bathroom or a shower.

Booster pumps are smaller and less expensive than replacing your main pump, and they can be installed on a single line or on the whole-house system. They work best when pressure is already adequate but not quite high enough; if your main pump is severely undersized, a booster will not solve the root problem. A pump technician can assess whether a booster makes sense for your situation and install it correctly so it does not damage your pipes or fixtures.

Frequently Asked Questions

Can I adjust the pressure switch myself?

Yes, adjusting the cut-out setting is a straightforward task if you are comfortable working with basic tools. Turn off the pump first, and make small adjustments — a quarter turn at a time — so you do not overpressurize the system. If you are unsure which nut controls which setting, consult your pump manual or call a technician before you start.

What is the highest pressure I should set my pump to?

Most residential systems should not exceed 60 psi. Higher pressure can crack pipes, damage water heaters and appliances, and wear out fixtures faster. If you need pressure above 60 psi, your pump may be undersized for your needs, and a technician should evaluate whether a larger pump or booster is the right solution.

How do I know if my pressure tank is waterlogged?

Tap the tank with a wrench or hammer. A hollow, ringing sound means air is still inside. A dull, solid thud means the tank is full of water and needs to be drained and recharged. You can also check by turning off the pump and opening a faucet — if pressure drops very quickly, the tank is likely waterlogged.

Will a bigger pump always solve low pressure?

Not always. Before replacing the pump, rule out a waterlogged tank, a clogged intake line, or a stuck check valve — all of which are cheaper to fix. If those are not the problem, then a larger pump or a booster pump may be needed, but a technician should diagnose the issue first.

How often should I recharge my pressure tank?

A healthy tank should hold its air charge for years. If you find yourself recharging it more than once a year, the bladder or diaphragm inside is likely failing and the tank should be replaced. Frequent recharging is a sign the tank is near the end of its life.