Fire pumps are vital components of any building’s fire protection system. They provide the necessary pressure and flow to ensure water reaches sprinklers and hose reels during an emergency. However, like any mechanical equipment, fire pumps can develop problems over time—many of which, if not addressed, can lead to serious system failures during a fire event.
As a fire pump manufacturer with years of experience, we’ve observed recurring problems in fire pump systems that can compromise performance and safety. This article explores the most common fire pump issues, their root causes, and practical solutions to keep your fire protection system operating reliably.
Pump doesn’t activate when the pressure drops.
No audible alarms or indicators.
Faulty pressure switches.
Electrical control panel issues.
Improper settings in automatic start controls.
Lack of routine testing or commissioning errors.
Test pressure switches and replace if needed.
Inspect and maintain the control panel regularly.
Ensure the system is set to “auto” and the controller is energized.
Conduct weekly test runs per NFPA 25 standards.
Insufficient water pressure at sprinkler heads.
Jockey pump runs more frequently than normal.
Clogged suction strainers.
Obstructed or corroded piping.
Air leaks in suction line or air entrainment.
Impeller wear or damage.
Inspect and clean strainers regularly.
Conduct a flow test to determine blockage location.
Check for air leaks and ensure all joints are sealed.
Replace or repair worn impellers.
Hot casing or bearing housing.
Motor trips or shuts down unexpectedly.
Continuous running without water flow (dead-heading).
Improper lubrication of motor or bearings.
Misalignment between pump and motor shaft.
Inadequate ventilation.
Ensure proper circulation of water.
Lubricate bearings as recommended by the manufacturer.
Use laser alignment tools to align motor and pump shafts.
Maintain clean, cool, and dry motor rooms.
Pump does not shut off after pressure is restored.
Jockey pump doesn’t maintain pressure.
Leaks in the system causing pressure drops.
Pressure switch malfunction.
Incorrect controller settings.
Inspect entire system for leaks.
Replace defective pressure switches.
Calibrate the controller according to design pressure settings.
Loud banging, rattling, or humming during operation.
Visible movement of pump or baseplate.
Cavitation due to low NPSH (Net Positive Suction Head).
Misaligned couplings or loose mounting bolts.
Worn bearings or unbalanced impellers.
Verify proper suction pressure and reduce inlet restrictions.
Realign pump and motor using appropriate tools.
Replace worn mechanical parts and re-balance impellers.
Secure all mounting hardware to reduce vibration.
Engine does not crank or stalls shortly after starting.
Alarm indicator on controller panel.
Dead battery or corroded terminals.
Empty or contaminated fuel tank.
Faulty starter motor.
Insufficient oil or coolant.
Perform regular battery checks and replace batteries annually.
Keep fuel tanks full and clean; inspect fuel filters.
Test starter motor function during weekly diesel pump test.
Follow manufacturer guidelines for oil and coolant maintenance.
Pump stops running unexpectedly.
Circuit breakers or overload relays trip.
Electrical short circuits or overloads.
Phase imbalance or single-phasing.
Grounding issues.
Use infrared thermography to identify overheating components.
Balance the voltage across all three phases.
Ground all electrical components per NFPA 70 and local codes.
Install proper surge protection.
No display or inaccurate readings.
Inability to switch between auto/manual mode.
Software glitches or firmware corruption.
Water ingress or moisture accumulation.
Aging control components.
Perform controller diagnostics and update firmware.
Keep control panels sealed and dry.
Replace outdated or corroded control modules.
Pump loses prime.
Irregular pressure readings or surging flow.
Improper priming.
Air leaks in suction piping.
Poor system design (e.g., high points in piping).
Prime the pump before operation.
Seal all joints and gaskets.
Install air release valves at system high points.
Frequent breakdowns.
Reduced pump lifespan.
Fire pump fails during actual fire emergency.
Lack of scheduled inspections and testing.
Failure to follow NFPA 25 or manufacturer’s guidelines.
Untrained personnel performing maintenance.
Develop and follow a detailed preventive maintenance schedule.
Train staff or contract certified technicians.
Document all maintenance and testing activities.
While individual issues may vary, most fire pump problems stem from poor maintenance, improper installation, or lack of routine testing. Here are some best practices to minimize risks:
Follow NFPA 20 and NFPA 25 Standards: These codes provide clear guidance on fire pump installation, testing, and maintenance requirements.
Conduct Weekly, Monthly, and Annual Inspections: Routine checks catch small problems before they become major failures.
Invest in Quality Components: Use UL-listed or FM-approved pumps and controllers from reputable manufacturers.
Train Operators and Technicians: Ensure that maintenance and inspections are carried out by qualified personnel.
Keep Accurate Records: Document all inspections, test results, and repairs to comply with audits and ensure accountability.
Fire pump systems are critical in life safety applications, and their failure can have catastrophic consequences. The good news is that most fire pump problems are preventable through regular maintenance, proper installation, and routine testing.
By understanding the most common fire pump issues and how to troubleshoot them, building owners, facility managers, and fire safety professionals can ensure that their fire protection systems operate reliably when they are needed most.
If you're experiencing any of these issues or want to ensure your system stays in top condition, feel free to contact our technical team. As a trusted fire pump manufacturer, we’re here to help with everything from component supply to full fire pump system design and support.
