Why Well Water Pressure Drops and How to Fix It

Low water pressure in a well system usually comes from one of three sources: a pressure tank that has lost its air charge, a clogged sediment filter, or a pressure switch that needs adjustment. The good news is that most of these fixes take an afternoon and cost under $100 in parts. A pressure tank is the most common culprit—over time, the air bladder inside loses pressure, and the tank can no longer push water through your pipes at full force.

Before you call a well contractor, you can test and fix several things yourself. Start by checking what pressure your system is actually producing right now, then work through the most likely causes in order. Most homeowners find the problem within the first two steps.

Key Takeaways

  • A pressure gauge reading below 40 psi usually points to a failing pressure tank, which you can recharge with an air compressor in about 30 minutes.
  • Sediment filters and the well screen itself clog over time and restrict flow; replacing the filter or having the well cleaned can restore pressure when ready.
  • The pressure switch controls when the pump turns on and off; if it is set too low, the system will not build enough pressure to reach your fixtures.
  • Check your pressure tank air charge before replacing the tank itself, since recharging costs $20 and a new tank costs $500 to $1,500.

Test Your Current Water Pressure

Buy or borrow a water pressure gauge—they cost $10 to $20 at any hardware store and screw onto an outdoor faucet or laundry sink. Turn off all water use in the house, then screw the gauge onto the lowest faucet (usually outside or in the basement). Turn the faucet on slowly and read the number. Normal well pressure sits between 40 and 60 psi. If you are reading below 40 psi, the pressure tank is likely the problem. If you are reading 40 to 60 psi but water still feels weak at your shower or kitchen sink, the issue is probably a clogged filter or a blockage downstream.

Write down the number you see. You will use it to check whether your fix worked. Leave the gauge on the faucet so you can test again after each step.

Recharge the Pressure Tank Air Bladder

The pressure tank holds both water and air. The air acts like a spring, pushing the water out when the pump is off. Over months or years, this air bladder loses pressure and can no longer do its job. Recharging it is the fastest and cheapest fix.

First, turn off the pump at the breaker or switch. Open a faucet somewhere in the house to release all pressure from the tank—you will hear air hiss out. Locate the air valve on top of the pressure tank (it looks like a bicycle tire valve). Use an air compressor to add air until the gauge reads about 2 psi below your pump's cut-in pressure. If your pump turns on at 40 psi, charge the tank to 38 psi. If it turns on at 30 psi, charge to 28 psi. You can find your pump's cut-in pressure on the pressure switch itself—it will be labeled, or you can call your well contractor to confirm.

Turn the pump back on and check your pressure gauge again. If it now reads 40 to 60 psi, you have solved the problem. If pressure is still low, move to the next step.

Replace or Clean the Sediment Filter

Well water often carries fine sand and sediment. A filter catches this before it reaches your house, but over time the filter clogs and restricts water flow. If your pressure is still low after recharging the tank, a clogged filter is the next most likely cause.

Locate your sediment filter—it is usually a tall cartridge mounted near the pressure tank or at the well head. Turn off the pump. Unscrew the filter housing (it will have a large wrench-sized nut at the bottom) and pull out the cartridge. If it looks brown, tan, or dark instead of white or cream, it is clogged. Replace it with a new cartridge of the same size and micron rating (usually printed on the old one). Screw the housing back on hand-tight, then use a wrench to snug it another quarter turn. Do not over-tighten.

Turn the pump back on and test pressure again. A new filter often restores pressure when ready. If pressure is still low, the clog may be deeper in the well itself, and you will need a well contractor to pull and clean the well screen.

Adjust the Pressure Switch Settings

The pressure switch tells the pump when to turn on and off. If it is set too low, the pump will not run long enough to build full pressure. Most switches have two adjustment screws—one for cut-in pressure (when the pump starts) and one for cut-out pressure (when it stops).

To adjust, turn off the pump at the breaker. Locate the pressure switch—it is a small box mounted on or near the pressure tank with two wires running to the pump. You will see two nuts on top. The larger nut controls cut-out pressure; the smaller one controls cut-in. Turning either nut clockwise increases pressure. Start by turning the cut-in nut one-quarter turn clockwise, then turn the pump back on and test. If pressure is still low, turn it another quarter turn and test again. Do not turn more than one full rotation without testing, or you may set the pressure too high and damage fixtures or the tank.

Typical settings are 40 psi cut-in and 60 psi cut-out, meaning the pump starts at 40 and stops at 60. If you are unsure of your current settings, take a photo of the switch and call your well contractor before adjusting.

When to Call a Well Contractor

If you have recharged the tank, replaced the filter, and adjusted the switch but pressure is still below 40 psi, the problem is likely inside the well itself. The well screen may be clogged with sediment, or the pump may be failing. A contractor can pull the well and clean the screen (usually $300 to $800) or test the pump to see if it needs replacement.

You should also call a contractor if you hear the pump running constantly without building pressure, or if you see water leaking from the pressure tank. A constantly running pump usually means the tank is waterlogged (the air bladder has ruptured), and the tank will need to be replaced. Leaking tanks cannot be repaired and must be replaced as well.

Frequently Asked Questions

How do I know if my pressure tank air bladder is bad?

If the tank feels heavy and full of water when you shake it, or if you hear water (not air) come out when you open the air valve, the bladder has failed. A failed bladder cannot be recharged and the tank must be replaced. You can also check by measuring pressure before and after the pump runs—if pressure drops quickly after the pump stops, the tank is not holding air.

Can low water pressure damage my well pump?

A failing pressure tank can cause the pump to run constantly, which wears it out faster. If the pump runs without building pressure, turn it off and call a contractor—running it dry can damage the pump permanently. Recharging the tank or replacing a clogged filter usually stops constant running within hours.

What pressure is too high for a well system?

Pressure above 80 psi can crack pipes, burst water heaters, and damage fixtures. If your gauge reads above 80 psi, turn off the pump when ready and adjust the pressure switch down, or call a contractor. Most residential systems are set to cut out at 60 psi for safety.

Why does my water pressure drop only at certain times of day?

If pressure is fine in the morning but drops by evening, your tank is probably losing its air charge. This happens when the air bladder is slowly leaking. Recharge the tank and monitor pressure over a few days—if it drops again, the bladder needs replacement. If pressure drops only when multiple fixtures run at once, you may need a larger tank or pump.

Is it safe to adjust the pressure switch myself?

Yes, if you make small adjustments and test after each one. Turn the nut only one-quarter turn at a time. If you are uncomfortable working with electrical equipment, take a photo of the switch and have a contractor make the adjustment—it usually costs $50 to $100 and takes 15 minutes.