Where the pressure problem starts in a well system

Well water pressure drops when the pump cannot push water hard enough to reach your fixtures, or when air gets trapped in the pipes. The most common causes are a failing pressure tank, a pump that is undersized for your home's demand, a clogged intake screen, or a leak somewhere in the line between the well and your house. Before you buy new equipment, you need to know which one is actually broken—because replacing the wrong part wastes money and leaves you with low pressure anyway.

A well system works by storing pressurized water in a tank so the pump does not run every time you turn on a faucet. When pressure inside that tank drops below a set point (usually around 40 pounds per square inch), the pump kicks on and refills it. If the tank is waterlogged—meaning it has lost the air cushion that creates pressure—the pump will run constantly but water will still trickle out slowly.

Key Takeaways

  • Check your pressure gauge first: if it reads below 40 psi when the pump is running, the problem is usually the pressure tank or pump, not the pipes.
  • A waterlogged pressure tank is the most common cause and can often be fixed by draining it and letting air back in, costing nothing but time.
  • If the pump runs constantly but pressure stays low, the intake screen at the well may be clogged with sediment and needs cleaning.
  • Replacing a pressure tank costs $300 to $800 installed; replacing a pump costs $800 to $2,500, so diagnosis before purchase matters.
  • Air leaks in the supply line between the well and house will cause pressure to drop gradually and require finding and sealing the leak.

Reading your pressure gauge to find the real problem

Every well system has a pressure gauge mounted on or near the pressure tank. Turn on a faucet and watch the gauge. If pressure drops quickly and the pump does not turn on, the tank is likely waterlogged. If the pump turns on but pressure climbs very slowly and stays below 40 psi even when the pump is running, the pump itself may be failing or undersized.

Write down three numbers: the pressure when the pump first kicks on (the cut-in point), the pressure when the pump shuts off (the cut-out point), and the pressure when you have a faucet running. Most systems are set to cut in at 40 psi and cut out at 60 psi. If your cut-out is only 50 psi or lower, or if pressure drops to 20 psi when you run two faucets at once, you have a pressure problem that needs fixing.

If the gauge needle bounces wildly or the pump cycles on and off every few seconds, the tank is almost certainly waterlogged. A healthy tank should let the pump run for at least 30 seconds before shutting off.

Draining and recharging a waterlogged pressure tank

A waterlogged tank has lost the air pocket that cushions pressure. Fixing it means draining the tank completely, letting air back in, and refilling it. This is the cheapest fix and takes about an hour.

First, turn off the pump at the breaker. Open a faucet at the lowest point in your house to relieve pressure in the tank. Then locate the drain valve at the bottom of the tank (it looks like a garden hose spigot) and open it fully. Let the tank drain completely—this may take 10 to 20 minutes depending on tank size. Once it stops dripping, close the drain valve.

Now turn the pump back on at the breaker. The pump will run and refill the tank with water. Watch the pressure gauge. It should climb steadily to 60 psi and then the pump should shut off. If pressure climbs normally and the pump shuts off cleanly, the tank is fixed. If the pump runs for more than a minute and pressure barely moves, the tank itself is damaged and needs replacement.

If the tank is fixed but pressure is still low when you run multiple faucets, move on to checking the intake screen or the pump size.

Cleaning a clogged intake screen at the well

The intake screen sits at the bottom of the well pipe and filters out sediment and sand. Over years, it clogs with fine particles and restricts water flow. The pump runs harder but less water gets through, so pressure stays low even though the pump is working.

To check the screen, you need to pull the pump and pipe assembly out of the well. This is a two-person job and requires a pipe wrench and a way to support the weight—a tripod or come-along hoist works. If you are not comfortable working at height or handling heavy pipe, hire a well service company to do this step. Cleaning the screen costs $150 to $400 if a professional does it, versus $0 if you do it yourself but takes several hours.

Once the pipe is out, unscrew the intake screen from the bottom of the pipe. Soak it in a bucket of clean water and scrub it with a soft brush to remove sediment. Rinse it thoroughly under running water until the water runs clear. Screw it back on, lower the pipe back into the well, and reconnect the pump. Turn the pump on and check pressure again.

Checking for air leaks in the supply line

If pressure is normal at the tank but drops significantly by the time water reaches your house, air is leaking into the line somewhere between the well and your home. Air pockets reduce the amount of water that can flow through the pipe.

Look for visible cracks or loose fittings on any exposed pipe, especially where the line enters your house or runs through the basement. Tighten any loose fittings with a wrench—turn clockwise. If you see a crack or pinhole, that section of pipe needs to be replaced. For underground lines, you may need to excavate and replace the damaged section, which is expensive. A plumber can pressure-test the line to pinpoint the leak location.

If all visible connections are tight and pressure is still dropping, the leak is likely underground and requires professional diagnosis with a pressure test.

When to replace the pump or tank

If you have drained and recharged the tank, cleaned the intake screen, and checked for leaks, but pressure is still below 40 psi when the pump is running, the pump itself is failing or undersized for your home's water demand.

A pump that is undersized will run constantly and never build enough pressure to shut off. This happens most often when a home has been expanded or when a second bathroom or outdoor faucet has been added without upgrading the pump. Replacing a pump costs $800 to $2,500 installed, depending on depth and pump type. A well service company can test the pump's output in gallons per minute and recommend the right size for your home.

A pressure tank that is truly damaged (not just waterlogged) will not hold pressure even after draining and recharging. The internal bladder has failed and cannot be repaired. Replacement tanks cost $300 to $800 installed. Tanks typically last 10 to 15 years, so if yours is older than that and pressure problems started recently, replacement is likely the answer.

Adjusting the pressure switch if pressure is too high

Sometimes the problem is the opposite: pressure is too high and strains fixtures and appliances. Most pressure switches are set to cut out at 60 psi, but they can be adjusted higher or lower.

Locate the pressure switch, which is usually a small box mounted on the pipe near the tank. It has a large nut on top. To lower the cut-out pressure, turn that nut counterclockwise one-quarter turn at a time. Turn the pump on, let it run until it shuts off, and check the gauge. Repeat until pressure is where you want it. Do not adjust more than one-quarter turn at a time or you may overshoot.

If you are uncomfortable adjusting the switch yourself, a plumber can do it in 15 minutes for $75 to $150. Adjusting the switch does not fix an underlying problem—if pressure is too high because the tank is failing, adjustment is temporary and you will still need a new tank eventually.

Frequently Asked Questions

How do I know if my well pump is failing?

A failing pump will run constantly or cycle on and off every few seconds, but pressure will stay below 40 psi even when the pump is running. The pump may also make grinding or squealing noises. If the tank is not waterlogged and the intake screen is clean, a pump that cannot build pressure needs replacement.

Can low water pressure damage my well pump?

No, but a pump that runs constantly trying to build pressure will wear out faster. Constant running generates heat and stress on the motor. If you notice the pump cycling rapidly, fix the underlying problem—usually a waterlogged tank—as soon as you can to extend the pump's life.

What is the normal pressure range for a well system?

Most systems are set to cut in at 40 psi and cut out at 60 psi. This range is comfortable for household use and does not strain fixtures. Some people prefer 50 to 70 psi for stronger shower pressure, but anything above 80 psi can damage appliances and should be reduced with a pressure regulator.

Will adding a second pressure tank increase water pressure?

A second tank will increase the amount of water available before the pump needs to run again, but it will not increase pressure itself. Pressure is created by the pump and the air cushion in the tank, not by tank size. If your pressure is low, a second tank will not fix it.

How often should I drain my pressure tank?

If your water is very sediment-heavy, draining once a year helps prevent waterlogging. In most homes with normal water quality, draining every two to three years is enough. If you notice pressure dropping gradually over weeks or months, drain the tank to see if that restores it.