Well Pump Not Building Pressure: Fix It Fast

1. Check Power and Circuit Breaker (Start Here)

A tripped breaker or blown fuse will prevent the pump motor from running entirely, making this the fastest and cheapest thing to rule out before diagnosing anything else.

1. Go to your electrical panel and locate the breaker labeled for the well pump (typically 240V, double-pole, 15–30 amp).
2. If the breaker is tripped (middle position), switch it fully OFF, then firmly back ON.
3. Check for a separate fused disconnect box near the pressure tank and inspect those fuses.
4. Reset power, then check your pressure gauge — the pump should kick on below the cut-in pressure (commonly 30 PSI).
5. If the breaker trips again immediately, stop and call an electrician — there may be a short in the motor wiring.

2. Inspect and Adjust the Pressure Switch

The pressure switch tells the pump when to start and stop; if its contacts are burned or its settings are off, the pump will not maintain the correct cut-in and cut-out pressure.

1. Turn off power to the pump at the breaker before opening the pressure switch cover.
2. Remove the plastic cover on the pressure switch (usually one screw) and look for burned, pitted, or corroded contacts — discoloration or blackening is a clear sign of failure.
3. With power OFF, use a multimeter set to continuity mode to confirm the contacts open and close properly as you manually depress the diaphragm.
4. If contacts are burned, replace the switch. Common settings are 30/50 PSI or 40/60 PSI (cut-in/cut-out).
5. If simply adjusting, turn the large nut clockwise to raise both cut-in and cut-out; turn the small nut clockwise to increase the differential (gap between cut-in and cut-out). Always consult the label inside the switch cover for the correct direction.
6. Restore power and watch the gauge to confirm the pump cycles in the correct range.

3. Test and Recharge the Pressure Tank (Well Pump Not Building Pressure Fix)

A waterlogged pressure tank — one that has lost its air charge — forces the pump to short-cycle and can make it appear as though the pump is failing to build adequate pressure.

1. Turn off power to the pump and open a nearby faucet to relieve all water pressure in the system until the gauge reads 0 PSI.
2. Locate the Schrader valve (looks like a tire valve) on the top or side of the pressure tank.
3. Use a tire pressure gauge to check the tank’s air charge. The pre-charge should be 2 PSI below the pump’s cut-in pressure (e.g., 28 PSI for a 30/50 system).
4. If the reading is low, add air with a bicycle pump or compressor until it reaches the correct pre-charge.
5. If water spurts out of the Schrader valve instead of air, the internal bladder has ruptured and the tank must be replaced.
6. Restore power, close the faucet, and watch the gauge cycle up to the cut-out pressure.

4. Inspect the Check Valve and Foot Valve

A faulty check valve allows pressurized water to flow back down into the well, causing pressure to bleed off quickly after the pump stops running.

1. Note your pressure gauge after the pump reaches cut-out pressure, then turn off the pump and watch the gauge over 10–15 minutes.
2. If pressure drops steadily with no faucets open, a failed check valve is the prime suspect.
3. Locate the inline check valve on the discharge pipe leaving the pump or pressure tank (on a jet pump system it is typically just above the pump).
4. Shut off power. Use a pipe wrench to remove the check valve, and test it by hand — it should allow flow only in one direction and spring back firmly.
5. Replace the check valve if it feels loose, doesn’t seat fully, or shows corrosion.
6. For a submersible pump, the foot valve is at the bottom of the drop pipe inside the well — inspect it only if you are pulling the pump for another reason, as extraction is a significant project.

5. Check for a Clogged Inlet Screen or Sediment Filter

Heavy sediment, iron deposits, or debris can partially clog the pump’s inlet screen or any inline sediment filter, severely restricting water flow and limiting how much pressure the pump can generate.

1. Locate the whole-house sediment filter housing (if installed) on the supply line before the pressure tank.
2. Shut off pump power, relieve pressure, then unscrew the filter housing and remove the cartridge.
3. Hold the cartridge up to light — if it is visibly brown, clogged, or collapsed, replace it.
4. On a jet pump, inspect the brass jet body (accessible by removing the front cover) for mineral scale or sand — clear it with a thin wire or replace if damaged.
5. If you have well water high in iron or sediment, increase your filter replacement schedule to every 1–3 months.

6. Diagnose a Worn or Failing Pump

If all other components check out, the pump itself — particularly a worn impeller or motor winding — may no longer be capable of generating adequate pressure.

1. With power on, listen at the well casing or pressure tank for the pump: a humming sound with no pressure build-up often signals a seized motor or burned capacitor.
2. For a jet pump, check the pump’s amp draw with a clamp meter at the breaker — compare to the motor nameplate rating. Significantly high amps suggest a mechanical bind; significantly low amps suggest a worn impeller.
3. Check the capacitor on single-phase motors (a cylindrical component inside the motor housing) — a bulging or leaking capacitor must be replaced before further diagnosis.
4. If the pump motor is more than 10–15 years old and other repairs haven’t solved the problem, replacement is usually more cost-effective than repair.
5. Submersible pump replacement requires pulling the drop pipe from the well — this is typically a two-person job and may require a well service contractor.

Repair vs. Replace Cost Guide

For additional guidance on well system maintenance and water safety, visit the CDC’s Private Well Maintenance resource.

Frequently asked questions