Well Pump Running Continuously: Troubleshooting and Repair
A well pump that runs without shutting off is one of the most operationally urgent failure modes in private water systems, signaling that the pump cannot reach the system's cut-off pressure or that pressure is being lost faster than the pump can build it. Left unaddressed, continuous operation burns out pump motors, collapses pressure tank bladders, and can draw a well dry. This page covers the primary causes of continuous pump operation, the diagnostic sequence used to isolate each cause, and the decision criteria that separate a field repair from a component replacement or professional service call.
Definition and scope
A well pump is designed to cycle: it runs until system pressure reaches the cut-off setpoint on the pressure switch, then shuts off until demand drops the pressure to the cut-in setpoint. The standard residential pressure switch is factory-set at 30/50 psi (cut-in/cut-off) or 40/60 psi, though adjustable models cover a broader range (Pumptec, NEMA standards context). When the pump runs continuously, it has failed to reach the cut-off setpoint within any observable cycle period — typically defined operationally as running longer than 30 minutes without shutting off under normal household demand.
The scope of this failure mode spans the entire pressure delivery chain: the pump and motor assembly, the drop pipe and check valves, the pressure tank and bladder, the pressure switch and its sensing port, and the well itself. Understanding which segment of that chain is responsible determines whether the repair is a simple adjustment or a pull-and-replace operation. Related failure modes — including well pump cycling too frequently and well pump low water pressure — share some upstream causes but have distinct diagnostic paths.
How it works
The pressure regulation loop in a residential well system operates as follows:
- Pump energizes when system pressure falls to the cut-in setpoint (commonly 30 or 40 psi).
- Water is delivered from the pump through the drop pipe, through a check valve, and into the pressure tank.
- Pressure tank pre-charge (the air bladder or diaphragm, factory-set to 2 psi below the cut-in setpoint) compresses as water volume increases.
- Pressure switch reads rising system pressure through a sensing port (typically a ¼-inch NPT tap on the tank tee).
- Contacts open at the cut-off setpoint, de-energizing the pump.
- Demand draws down pressure from the tank until the cut-in setpoint is reached, restarting the cycle.
Continuous operation means the pump is energized throughout steps 1–4 without ever triggering step 5. The pump either cannot generate sufficient pressure to reach the cut-off point, or pressure is escaping the system as fast as it is being produced, or the pressure switch contacts are stuck closed and the sensing circuit is not functioning. Well pump pressure switch repair and well pump pressure tank problems address two of the three primary intervention points in this loop.
Common scenarios
Waterlogged or failed pressure tank
A waterlogged tank — one in which the air bladder has ruptured or lost pre-charge — fills entirely with water and loses its buffer capacity. The pump runs continuously because there is no stored air volume to build pressure against. A tank bladder can be tested by pressing the Schrader valve on the tank's air fitting: if water exits instead of air, the bladder has failed. Pre-charge pressure should measure within 2 psi of the cut-in setpoint when the system is depressurized (Well Water Journal, Pressure Tank Diagnostics).
Failed or missing check valve
A check valve holds pressure in the system when the pump is off. A leaking check valve — whether at the pump outlet, at the pitless adapter, or in the drop pipe — allows pressurized water to bleed back into the well, continuously depressurizing the system. The pump then runs without shutting off because it can never accumulate pressure past cut-off. Well pump check valve repair covers replacement procedures for both submersible and jet pump configurations.
Pressure switch malfunction
A clogged sensing port (mineral scale or biofilm blocking the ¼-inch port) prevents the switch from reading actual system pressure. The contacts may also be welded shut from arcing, which is a hazard documented under NFPA 70 (National Electrical Code, 2023 edition) Article 430, governing motor branch circuit protection. A switch with welded contacts will not open regardless of system pressure.
Worn pump or motor producing insufficient pressure
A pump that is mechanically worn — impellers eroded by sand, bearings worn, or motor windings degraded — may run indefinitely but never develop sufficient head pressure to reach cut-off. Well pump motor failure and well pump sand and sediment problems detail the degradation pathways that reduce pump output over time. Submersible pump lifespan averages 8–15 years depending on water quality and cycling frequency (per Water Systems Council).
Low well yield (well running dry)
If the well's recovery rate is lower than the pump's draw rate, the pump runs in air or low-water conditions without building pressure. This scenario is distinct from mechanical pump failure and requires a well pump flow rate testing assessment and potentially a well yield evaluation.
Decision boundaries
The following framework separates field-serviceable repairs from professional interventions:
| Condition | DIY/Field Serviceable | Licensed Contractor Required |
|---|---|---|
| Pressure switch clogged sensing port | Yes — clean or replace switch | No, unless wiring is involved |
| Waterlogged pressure tank (bladder tank replacement) | Yes — if system is de-energized and depressurized | Recommended for tanks >80 gallons |
| Check valve replacement (above-grade) | Yes | No |
| Check valve replacement (submersible, below pitless) | No — requires pump pull | Yes |
| Pump worn / insufficient head pressure | No | Yes — pump pull and replacement |
| Low well yield diagnosis | No | Yes — licensed well driller or hydrogeologist |
| Pressure switch wiring repair | Only with NFPA 70 compliance | Preferred |
Permitting requirements vary by jurisdiction. Most states regulate well pump work through their department of environmental quality or department of health. Pulling and resetting a submersible pump typically requires a licensed well contractor under state well codes — see well pump repair permits and regulations for a state-by-state overview. The Water Systems Council's Wellcare program provides model standards that many state agencies reference for well maintenance and repair thresholds.
Safety framing: Any electrical work on well pump systems must comply with NFPA 70 (National Electrical Code, 2023 edition) and, where applicable, OSHA 29 CFR 1910.303 for electrical safety in general industry. Note that individual jurisdictions adopt NEC editions on their own schedules and may still be enforcing an earlier version — verify the adopted edition with the local authority having jurisdiction (AHJ). Pump systems operating at 240V require proper lockout/tagout procedures before any inspection of the pressure switch, control box, or wiring. Well pump wiring and electrical issues addresses the electrical side of continuous-run diagnosis in detail.
References
- Water Systems Council — Wellcare Program
- NFPA 70: National Electrical Code, 2023 edition, Article 430
- OSHA 29 CFR 1910.303 — Electrical Safety Standards
- NEMA — Pump and Motor Standards Overview
- Well Water Journal — Pressure Tank Diagnostics
- EPA — Private Drinking Water Wells