Why Your Well Pressure Drops and What You Can Do About It

Low water pressure on a well usually comes from one of three places: a problem with the pressure tank, a clogged or failing pump, or sediment buildup in the system. You can often fix it yourself by checking the air charge in your pressure tank first—this is the easiest step and solves the problem about half the time. If that does not work, the next move is to inspect the pump and pressure switch, then work toward cleaning or replacing components if needed.

The good news is that you do not need to call a well contractor for every pressure drop. Some fixes take an afternoon and cost under $50. Others require professional help, but knowing what to check first saves you money and narrows down what a technician needs to do.

Key Takeaways

  • A pressure tank loses its air charge over time, and refilling it with a bicycle pump or compressor often restores normal pressure without any other work.
  • Pressure tanks typically maintain water pressure between 40 and 60 pounds per square inch (PSI), and your gauge should show this range when the pump is off.
  • Sediment in the well or a failing pump can lower pressure gradually, and flushing the system or replacing the pump may be necessary if the tank air charge is normal.
  • The pressure switch tells the pump when to turn on and off, and a stuck or misaligned switch can prevent the pump from running or cause it to cycle too often.
  • If pressure is low only at certain fixtures, the problem is likely in your home's plumbing, not the well itself.

Check and Refill Your Pressure Tank's Air Charge

Your pressure tank holds both water and air. The air acts like a spring, pushing water out of the tank and into your home when you turn on a faucet. Over months or years, this air charge leaks away or gets absorbed into the water, and pressure drops. Refilling the air is often the fastest fix.

First, turn off the pump at the pressure switch or circuit breaker. Locate the air valve on top of the pressure tank—it looks like a tire valve on a car. Use a tire pressure gauge to check the current air pressure inside the tank. The air pressure should be about 2 PSI lower than the pressure switch's cut-in point (usually 38 PSI if your switch is set to 40 PSI). If the gauge reads zero or very low, the air charge is gone.

Use a bicycle pump or an air compressor to add air back into the tank. Pump slowly and check the pressure every few strokes. Stop when you reach the target pressure—usually 2 PSI below your cut-in setting. Turn the pump back on and check your water pressure at a faucet. In many cases, this single step restores normal pressure.

Test Your Pressure Switch and Gauge

The pressure switch sits near the pressure tank and tells the pump when to start and stop. If it is stuck, misaligned, or failing, the pump may not run at all, or it may run constantly without building pressure. A faulty gauge can also make you think pressure is low when it is actually normal.

Watch the gauge while someone turns on a faucet inside the house. The pressure should drop, and the pump should kick on automatically. When the faucet closes, pressure should rise back to the cut-out point (usually 60 PSI), and the pump should shut off. If the pump does not start when pressure drops, or if it does not stop when pressure rises, the switch needs adjustment or replacement.

Test the gauge itself by comparing it to a second gauge borrowed from a neighbor or purchased for $10 to $15. Screw the new gauge onto the test port on the pressure tank (or onto the gauge itself if there is a port). If the readings differ by more than 5 PSI, your original gauge is inaccurate and should be replaced. If both gauges agree and pressure is truly low, move on to checking the pump and intake lines.

Inspect the Pump and Intake Line for Clogs

Sediment, sand, or mineral buildup can clog the intake line that runs from the well to the pump, or it can damage the pump itself. A clogged intake line forces the pump to work harder and deliver less water. A failing pump straightforward cannot build pressure no matter how hard it runs.

If you have a shallow well (less than 25 feet deep), you may have an intake line with a foot valve and screen at the bottom. Sediment can clog this screen. Turn off the pump, disconnect the intake line at the pump, and look inside. If you see sand or sediment, you can try flushing the line by running clean water backward through it with a garden hose. This works sometimes but not always.

For deep wells, the pump sits inside the well casing, and you cannot easily inspect it yourself. However, you can listen for signs of trouble. A pump that runs constantly but delivers very little water, or one that makes grinding or squealing sounds, is likely failing. A pump that does not run at all may have a tripped breaker, a bad capacitor, or an internal failure. At this point, a well contractor should inspect the pump and pressure tank together to determine whether repair or replacement is needed.

Flush the System to Remove Sediment

Sediment inside the pressure tank or plumbing lines can reduce flow and pressure throughout your home. Flushing the system can help, though it works best if the sediment is loose rather than packed into the tank.

Turn off the pump. Locate the drain valve at the bottom of the pressure tank (or at the lowest point in your plumbing). Attach a garden hose and open the valve fully. Let water run until it runs clear—this may take 10 to 30 minutes. Close the drain valve, turn the pump back on, and check pressure at a faucet.

If pressure is still low and you suspect sediment in the well itself, you can hire a well contractor to perform a more thorough flush or to pull and clean the pump. This is more expensive but necessary if sediment is coming from the well rather than from inside your tank or plumbing.

Adjust the Pressure Switch if Needed

If your pressure switch is working but set too low, you can adjust it to raise the pressure range. Most switches have two nuts on top: one controls the cut-in pressure (when the pump starts) and one controls the differential (the gap between cut-in and cut-out).

Before adjusting, turn off the pump. Use a wrench to turn the larger nut clockwise to raise the cut-in pressure. Make small adjustments—one-quarter turn at a time—and turn the pump back on to test. The typical range is 40 to 60 PSI, so do not raise it beyond 60 unless your tank and plumbing are rated for higher pressure. Raising pressure too high can damage fixtures and cause the pump to cycle too often, shortening its life.

If you are not comfortable adjusting the switch, or if adjustment does not help, a well contractor can do this work and verify that all settings are correct for your system.

Know When to Call a Professional

Call a well contractor if the pressure tank air charge is normal, the pressure switch is working, and pressure is still low. This usually means the pump is failing, the well itself has a problem, or there is a significant clog in the intake line. A contractor has tools to measure pump output, test the well's recovery rate, and pull the pump if needed.

Also call a professional if you hear the pump running constantly, if pressure fluctuates wildly, or if the pump makes unusual noises. These are signs of internal pump failure or a problem with the well that you cannot fix with basic maintenance.

Frequently Asked Questions

How often should I check the air pressure in my pressure tank?

Check it once a year, ideally in the fall before winter. If you notice pressure dropping over a few months, check it more often. A tank that loses air charge repeatedly may have a slow leak in the valve itself, which a contractor can repair.

What if pressure is low only at one faucet or shower?

The problem is in your home's plumbing, not the well. Check for a clogged aerator on the faucet, a closed shut-off valve under the sink, or a kinked supply line. If multiple fixtures in one area are slow, a clogged section of pipe may need to be replaced.

Can I increase pressure by raising the pressure switch setting above 60 PSI?

You can, but it is not recommended. Most home plumbing is rated for 80 PSI maximum, and running at 60 to 70 PSI is already on the high end. Higher pressure stresses pipes, fixtures, and the pump itself, leading to leaks and premature failure. If you need more pressure, the pump or tank may be undersized for your home's needs.

Why does my pressure tank have water coming out of the air valve?

Water in the air valve means the air charge is completely gone and the tank is full of water. Turn off the pump when ready and drain the tank completely using the drain valve. Refill the air charge to the correct pressure. If water keeps appearing in the air valve, the tank's internal bladder or diaphragm has failed and the tank needs replacement.

How long does a well pump usually last?

A submersible pump in a deep well typically lasts 8 to 15 years depending on water quality and how often it runs. A shallow-well jet pump lasts 7 to 12 years. If your pump is older than 10 years and pressure is dropping, replacement may be more cost-effective than repair.