Troubleshooting
Pump Troubleshooting
Pump Troubleshooting in industrial control systems — covering 6 topic areas in the CurryControls.com controls and automation knowledge hub.
Written guides in this section
Full references, procedures, and diagnostic guides published under Pump Troubleshooting.
Pump Will Not Start
A pump that is called and does nothing. The order to check: permissives and mode, control power, the starter or drive, the motor circuit, and the pump itself, with the measurements that settle each one in minutes.
10 min readUpdated Sep 5, 2026
Pump Short Cycles
A pump that starts and stops far more often than it should: the control band, the level signal, a leaking check valve, a waterlogged pressure tank, a lag pump doing the lead job, and the starts-per-hour limit that makes short cycling a motor killer.
9 min readUpdated Sep 5, 2026
Pump Runs But No Flow
The motor turns and nothing moves. How to tell a clogged impeller from an air-bound pump, a closed valve, a stuck check, a broken coupling, or reverse rotation, using motor current and discharge pressure before pulling anything.
10 min readUpdated Sep 5, 2026
Pump Loses Prime
A suction-lift pump that runs without pumping, or pumps for a while and then stops: air leaking into the suction line, a foot valve that lets the line drain, a lift too high, a vortex or an aerated inflow, or a self-priming casing that lost its charge.
8 min readUpdated Sep 5, 2026
Seal Failure Alarm
The moisture probe in a submersible pump has tripped its relay: a seal that is leaking, or moisture in the cable, the junction box, or the probe circuit, a relay that does not match the pump, or a failed relay. What the alarm should do and what to check.
8 min readUpdated Sep 5, 2026
Both Pumps Running Constantly
A duplex station where lead and lag run together and never catch up: inflow beyond one pump, pumps that lost capacity to wear or rags, a force main partly blocked, a pump that runs but does not pump, a level stuck high, or bad setpoints. The drawdown test.
8 min readUpdated Sep 5, 2026
Topics in this area
Pump Will Not Start
Pump Will Not Start — practical reference notes for controls engineers, integrators, and technicians working with pump troubleshooting.
Pump Short Cycles
Pump Short Cycles — practical reference notes for controls engineers, integrators, and technicians working with pump troubleshooting.
Pump Runs But No Flow
Pump Runs But No Flow — practical reference notes for controls engineers, integrators, and technicians working with pump troubleshooting.
Pump Loses Prime
Pump Loses Prime — practical reference notes for controls engineers, integrators, and technicians working with pump troubleshooting.
Seal Failure Alarm
Seal Failure Alarm — practical reference notes for controls engineers, integrators, and technicians working with pump troubleshooting.
Both Pumps Running Constantly
Both Pumps Running Constantly — practical reference notes for controls engineers, integrators, and technicians working with pump troubleshooting.
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