Where Low Pressure Comes From in a Well System

A well system relies on a pump to push water from underground into your house. Low pressure usually means the pump is not moving water fast enough, the pressure tank has lost its air charge, or something is blocking the line. Unlike a municipal system where the water company maintains pressure for you, a well system puts that responsibility on your equipment — and when one part fails, pressure drops across the whole house.

The most common culprits are a waterlogged pressure tank (the air pocket inside has filled with water), a pump that is aging or running too slowly, sediment clogging the intake line, or a leak somewhere in the system that lets pressure escape. Occasionally the problem is simpler: a closed valve, a clogged filter, or a check valve that has stuck.

Key Takeaways

  • Check the pressure tank air charge first — most tanks lose pressure over time and need air added back in with a bicycle pump or compressor.
  • A pressure switch controls when the pump turns on and off; adjusting it upward can raise the pressure your system delivers, but only if the pump can handle it.
  • Sediment in the well intake or a clogged filter will choke pressure; flushing the line or replacing the filter often restores flow when ready.
  • If the pump itself is old or undersized, you may need to replace it rather than adjust settings — a well contractor can test the pump's output to confirm.
  • Leaks in buried lines or at fittings will defeat any adjustment; find and repair them before spending money on a new pump.

Check and Recharge Your Pressure Tank

The pressure tank stores water under air pressure so that when you turn on a faucet, water comes out without the pump running every few seconds. Over months and years, the air pocket inside the tank shrinks as air dissolves into the water or leaks out through the valve. When the air charge drops too low, the tank cannot hold pressure, and your system feels weak.

Look for a small valve on top of the tank — it looks like a tire valve on a car. Turn off the pump at the breaker and drain the tank by opening a faucet until water stops. Use a tire pressure gauge to check the air pressure inside the tank. Most residential tanks should read between 28 and 40 pounds per square inch (psi), depending on your system. If it reads below 20 psi or zero, the tank has lost its charge.

Use a bicycle pump or an air compressor to add air back in until the gauge reads about 2 psi below your system's cut-in pressure (the pressure at which the pump turns on — usually 30 to 40 psi). Turn the pump back on and check whether pressure at your faucets improves. This fix costs nothing and solves the problem in roughly half of low-pressure complaints.

Adjust the Pressure Switch Settings

The pressure switch is a small box mounted near the pressure tank. It tells the pump when to turn on (cut-in pressure) and when to turn off (cut-out pressure). If the switch is set too low, your system will never build up strong pressure. Raising the settings can increase the pressure you feel at your taps.

Locate the pressure switch and look for two adjustment nuts or screws — usually labeled or color-coded. The larger nut controls the cut-in pressure (when the pump starts); the smaller one controls the differential (the gap between cut-in and cut-out). Turn the larger nut clockwise a quarter turn at a time, then turn the pump back on and wait for it to cycle. Check the pressure gauge on the tank. Stop when you reach your target pressure, usually 50 to 60 psi for household use.

Do not raise the pressure above what your pump is rated for — check the pump nameplate or your well contractor's paperwork. Pushing the pump too hard shortens its life and can damage fittings and appliances downstream. If you cannot find the switch settings or are unsure, call a well contractor; adjusting it wrong can cause the pump to run constantly or fail to start.

Clear Sediment From the Well Intake and Filters

Sand, silt, and sediment from the well can clog the intake screen or the filter cartridge, restricting water flow and killing pressure. If pressure dropped suddenly rather than gradually, sediment is often the cause. You may also notice cloudy or discolored water.

Start by checking any sediment filter in your system — usually a clear bowl or cartridge near the pressure tank. If it looks dirty or brown, turn off the pump, close the isolation valve below the filter, and unscrew the bowl or cartridge. Rinse it with clean water or replace it if it is clogged. Turn the pump back on and test pressure.

If the filter was clean or pressure is still low, the problem may be at the well intake itself. This requires turning off the pump and opening the line that runs from the well to the house — a job best left to a well contractor, who has the tools to flush the line and clear the intake screen without contaminating the well. Flushing usually costs between $200 and $500 and can restore pressure when ready if sediment is the culprit.

Replace or Repair the Pump

If the pressure tank is charged, the switch is set correctly, and the lines are clear, the pump itself may be worn out or undersized. A pump that is 10 or more years old often loses efficiency. A pump that was never large enough for your household's peak demand will struggle to build pressure when multiple people use water at once.

A well contractor can test the pump's output — the number of gallons per minute it delivers — and compare it to what your system needs. If the pump is delivering less than 5 gallons per minute, replacement is usually the answer. A new pump costs $800 to $2,500 installed, depending on the depth of your well and the pump's size. Submersible pumps (which sit inside the well) are most common in residential systems.

Before replacing the pump, have the contractor check for leaks in the buried line or at fittings. A slow leak will defeat a new pump just as it defeats an old one, so fix the leak first.

Find and Repair Leaks in the System

A leak anywhere between the well and your house will cause pressure to drop and the pump to run more often. Leaks in buried lines are the hardest to spot but the most damaging. Signs include wet spots in the yard, unusually high water usage, or the pump running constantly even when no water is being used.

Check all visible fittings and connections near the pressure tank and pump for drips or moisture. Tighten any loose connections with a wrench. If you see water pooling in the yard or hear water running when all faucets are off, a buried line is likely leaking. This requires a well contractor with leak-detection equipment; they may need to excavate and replace a section of pipe, which can cost $500 to $2,000 depending on depth and length.

Do not ignore a leak while adjusting the pump or pressure switch. The leak will only get worse, and any pressure gain you make will be lost through the hole.

When to Call a Well Contractor

You can recharge the pressure tank and replace a filter yourself. Adjusting the pressure switch is possible if you are comfortable with basic tools, but a mistake can damage the pump. Everything else — testing pump output, flushing the well intake, finding buried leaks, or replacing the pump — requires a licensed well contractor.

A contractor will arrive with a pressure gauge, test equipment, and the knowledge to diagnose the problem without guessing. A service call usually costs $150 to $300 and often saves money by pointing you toward the real fix instead of a wasted repair. Ask the contractor to explain what they find and why they recommend a particular solution before you commit to work.

Frequently Asked Questions

How much water pressure should I have?

Most homes are comfortable with 40 to 60 psi. Below 30 psi, showers feel weak and filling a tub takes forever. Above 80 psi, you risk damage to fittings, water heaters, and appliances. Your pressure switch is usually set to cut in around 30 psi and cut out around 50 psi, giving you a range in the middle.

Can I increase pressure by adding a second pump?

No. A second pump will not help unless the first pump is too small for your well's output — a rare problem. More often, adding a pump creates conflicts in the system and causes both to work harder. A well contractor can test whether your pump is undersized before you spend money on equipment.

Why does my pressure drop when I use hot water?

Hot water lines are often smaller than cold lines, and the water heater itself can restrict flow. This is not a well problem. If pressure is normal at cold taps but weak at hot taps, have a plumber check the water heater and hot lines for blockages or undersized pipe.

How often should I recharge the pressure tank?

A healthy tank should hold its charge for years. If you are recharging it more than once a year, the tank itself is failing and needs replacement. A new tank costs $300 to $800 installed and will restore normal pressure if the tank was the problem.

What if pressure is fine in winter but drops in summer?

Heavy use in summer can overwhelm a pump that is too small or too slow. If pressure drops only when multiple people shower or water the lawn at once, the pump may be undersized for peak demand. A contractor can measure peak flow and recommend a larger pump if needed.