Why Your Well Pressure Drops and What You Can Do About It
Low water pressure in a well system usually comes from one of three places: the pressure tank has lost its air charge, the pump itself is failing, or sediment has clogged a filter or screen. You can fix the first two yourself in most cases. The third often requires a professional, but knowing which one you're dealing with saves you time and money.
A well system relies on a pressure tank to store water under pressure so your pump doesn't run constantly. When that tank loses its air cushion, the pump runs more often but delivers water at lower pressure. A failing pump straightforward can't push water hard enough. A clogged filter restricts flow before it reaches your house. Each has a different fix, and trying the wrong one wastes effort.
Key Takeaways
- Check your pressure tank's air charge first—it's the easiest fix and requires only a bicycle pump and a pressure gauge.
- If the tank is properly charged, test your pump's pressure switch to see whether the pump is turning on and off at the right pressures.
- Sediment in your well water can clog filters and screens; replacing or cleaning them may restore pressure without touching the pump.
- If pressure is low everywhere in the house at once, the problem is upstream (tank, pump, or filter); if it's low in one area only, check for leaks or blockages in that line.
- A pressure gauge costs under $20 and tells you whether your system is working within normal range (typically 40 to 60 pounds per square inch).
Check and Recharge Your Pressure Tank
The pressure tank sits between your pump and your house lines. Inside it are two chambers: one holds water, the other holds air. The air pushes back on the water, creating pressure. Over time, that air leaks out through a small valve at the top of the tank, and pressure drops.
To recharge it, you need a bicycle pump and a tire pressure gauge. First, turn off the pump at the breaker. Open a faucet in the house to release pressure from the tank—you'll hear air hiss out. Once it stops, locate the air valve on top of the tank (it looks like a tire valve). Attach your pressure gauge and read the current pressure. Most residential tanks should be charged to 2 pounds per square inch (psi) below your pump's cut-in pressure—typically 38 psi if your pump turns on at 40 psi.
If the reading is low or zero, use your bicycle pump to add air until you reach the target pressure. Reattach the gauge to confirm. Turn the pump back on and check your water pressure at a faucet with a pressure gauge. Normal household pressure is 40 to 60 psi. If pressure is now in that range, you've solved the problem. If it's still low, move to the next step.
Test Your Pump's Pressure Switch
The pressure switch tells your pump when to turn on and off. If it's stuck or miscalibrated, the pump may not build pressure correctly. You can test it without taking it apart.
Turn off the pump. Open a faucet and let water run until pressure drops to zero (you'll see it on a gauge attached to the tank). Close the faucet. Turn the pump back on and listen. The pump should start when ready and run until pressure reaches 60 psi (or whatever your upper limit is set to), then stop. If the pump doesn't start, starts but won't stop, or stops before reaching normal pressure, the switch needs adjustment or replacement.
Adjusting a pressure switch requires a wrench and a pressure gauge, and the steps vary by model. If you're not comfortable opening the switch housing, call a well service technician. A new switch costs $100 to $300 installed, and it's worth the cost if your pump is otherwise healthy.
Clean or Replace Clogged Filters and Screens
Sediment from your well can clog the intake screen at the bottom of your well, or filters in your pressure tank or pump discharge line. A clogged screen or filter restricts water flow and makes pressure drop throughout the house.
If you have a sediment filter in your system (a cartridge-style filter near the tank or pump), turn off the pump and close the isolation valve on the inlet side of the filter. Unscrew the filter housing and pull out the cartridge. If it's visibly dirty or discolored, replace it with a new one of the same micron rating. If it's only lightly soiled, you can rinse it with clean water and reinstall it. Reopen the isolation valve and turn the pump back on.
If pressure is still low and you suspect the well intake screen is clogged, you'll need a well service company to pull the pump and clean or replace the screen. This is not a DIY job—it requires specialized equipment and knowledge of your well's depth and construction. A technician can do it in a few hours, and the cost is typically $300 to $800 depending on how deep your well is.
Check for Leaks in Your Pressure Lines
If pressure is low in only one part of your house—say, the upstairs bathroom but not the kitchen—the problem is likely a leak or blockage in that branch line, not your pump or tank.
Turn off all faucets and appliances. Look at your water meter or the pump discharge gauge. If the reading is changing even though nothing is running, you have a leak. Trace the line to the affected area and look for wet spots in walls, under floors, or in crawl spaces. A pinhole leak in copper or PEX line is hard to spot but will show as dampness or discoloration on drywall or flooring.
If you find a leak, you can patch a small hole with epoxy putty as a temporary fix, but the line should be replaced. If you don't find a leak but pressure is still low in that area, a valve or fitting may be partially blocked. Shut off the isolation valve for that line (if one exists), then open it fully. If pressure improves, the valve was the culprit. If not, sediment may be stuck inside the line, and a plumber can flush it or replace the affected section.
When to Call a Well Service Professional
Call a well technician if your pressure tank is properly charged and your pump's pressure switch is working, but pressure is still low everywhere in the house. The pump itself may be worn out, or the well may be running low on water (common in drought or in older wells). A technician can measure the water level in your well and test the pump's output to tell you whether the pump needs replacement or whether your well needs rehabilitation.
Also call a professional if you're uncomfortable working with pressure gauges, opening tank housings, or handling electrical components. A pressure switch adjustment or tank recharge takes a technician 30 minutes to an hour and costs $100 to $200 in service fees. That's worth paying to avoid damaging your system or injuring yourself.
Frequently Asked Questions
How often should I check my pressure tank's air charge?
Check it once a year, ideally in the fall before winter. If you notice pressure dropping over a few weeks, check sooner. A slow air leak is normal; a complete loss of charge in days suggests a faulty valve and means the tank should be serviced.
Can low water pressure damage my pump?
No, but a pump running constantly because the pressure tank is dead will wear out faster. A dead tank forces the pump to cycle on and off dozens of times per hour instead of a few times, shortening its lifespan by years. Recharging the tank protects the pump.
What's the difference between a pressure tank and a pressure switch?
The tank stores pressurized water. The switch is an electrical device that tells the pump when to start and stop. You need both working correctly for normal pressure. A bad tank makes pressure drop slowly; a bad switch makes pressure erratic or stuck.
Is it safe to add air to my pressure tank myself?
Yes, if you follow the steps: turn off the pump, release pressure from the system first, and use a bicycle pump with a gauge. Never use an air compressor—the pressure can exceed what the tank is rated for and cause damage or injury.
Why does my well pressure drop after I use a lot of water?
Your pressure tank can only store so much water. If you run multiple showers or fill a bathtub, you drain the tank faster than the pump can refill it. Pressure drops until the pump catches up. This is normal. If pressure takes more than a few minutes to recover, your pump may be undersized or failing.