How to Test Fire Pumps for Maximum Efficiency

Fire pumps are the heart of any fire protection system, responsible for supplying the necessary water pressure to safeguard people and property during emergencies. However, even the most advanced fire pump systems can underperform if they are not regularly tested and maintained. To ensure your fire pump system operates at its peak, routine fire pump testing is critical.

This guide explains how to test fire pumps for maximum efficiency, following NFPA 25 standards, step-by-step procedures, and performance analysis techniques. Whether you operate electric fire pumps, diesel engine pumps, or vertical turbine fire pumps, the following strategies will help you maintain system reliability and meet safety compliance requirements.

1. Why Fire Pump Testing Matters

Fire pumps are typically idle most of the time and only activate during an emergency. Without regular performance testing, you cannot be sure that your system will function properly when needed. Proper fire pump testing ensures:

• Maximum Efficiency: Verifies that pumps deliver required flow and pressure.

• Safety Compliance: Meets NFPA 20 and NFPA 25 standards.

• Early Problem Detection: Identifies mechanical issues before they become critical failures.

• Extended Equipment Life: Prevents wear and tear from unnoticed defects.

NFPA 25, the standard for inspection, testing, and maintenance of water-based fire protection systems, requires annual fire pump flow testing and weekly or monthly inspection runs depending on pump type.

2. Key Types of Fire Pump Tests

Fire pump testing involves multiple assessments to ensure optimal performance. These are the most common tests used in the fire safety industry:

2.1. No-Flow (Churn) Test

• Purpose: Ensures the pump operates smoothly without water flowing.

• Procedure: Run the pump with the discharge valve closed, checking for vibration, unusual noise, overheating, and proper pressure readings.

• Frequency: Weekly for diesel pumps, monthly for electric pumps.

2.2. Flow Test (Annual Performance Test)

• Purpose: Evaluates pump performance under actual operating conditions.

• Procedure:

  1. Connect hoses to the test header or hydrants.

  2. Measure water flow at 100%, 150%, and 0% of rated capacity.

  3. Compare results with manufacturer specifications.

• Frequency: Annually, per NFPA 25.

2.3. Pressure Relief Valve Test

• Ensures relief valves open at the correct set pressure, preventing overpressure situations.

2.4. Diesel Engine Fire Pump Test

• Check oil levels, cooling system, fuel supply, and battery status.

• Start the engine and monitor RPM, pressure, and water flow.

2.5. Electric Motor Fire Pump Test

• Inspect insulation, motor windings, and starter performance.

• Test for proper voltage, amperage, and alignment with pump load.

3. Step-by-Step Fire Pump Testing Procedure

To maximize testing accuracy and efficiency, follow this structured approach:

Step 1: Pre-Test Inspection

• Check suction and discharge valves for proper positioning.

• Inspect packing glands, bearings, and mechanical seals for leaks.

• Verify gauges, flow meters, and sensors are calibrated.

Step 2: Record Baseline Readings

• Static suction pressure

• Discharge pressure

• Pump speed (RPM)

• Motor amperage

Establishing a baseline helps you compare results over time and detect performance trends.

Step 3: Conduct the Flow Test

• Open test headers gradually to avoid water hammer.

• Measure discharge pressure, suction pressure, and water flow at:

  • 100% capacity (normal demand)

  • 150% capacity (overload)

  • Shutoff (0% flow)

Step 4: Monitor Pump Performance

• Check for excessive vibration, overheating, or cavitation.

• Verify the driver (diesel/electric) reaches proper speed.

• Ensure the relief valve operates correctly under high pressure.

Step 5: Record and Analyze Results

• Compare test data to the pump’s original acceptance test curves.

• Any deviation greater than 5% may indicate performance deterioration.

• If results are below standards, schedule corrective maintenance immediately.

4. NFPA 25 Requirements for Fire Pump Testing

The NFPA 25 standard outlines the minimum requirements for fire pump testing:

Following these guidelines ensures compliance, safety, and readiness.

5. Common Problems Detected During Fire Pump Testing

Routine testing often reveals performance issues that might otherwise go unnoticed:

• Low discharge pressure – Caused by impeller wear, clogged suction, or faulty valves.

• Excessive vibration – May indicate misalignment or bearing failure.

• Overheating motor or diesel engine – Usually related to lubrication or cooling problems.

• Relief valve malfunction – Can lead to dangerous overpressure situations.

• Air leaks on suction lines – Reduce pump efficiency and cause cavitation.

Identifying these problems early reduces costly downtime and ensures reliable fire protection.

6. Best Practices to Maximize Fire Pump Efficiency

• Schedule Testing During Low-Demand Hours: Avoid disrupting facility operations.

• Use Calibrated Instruments: Accurate gauges and flow meters ensure reliable results.

• Maintain Detailed Test Records: Documenting every test builds a performance history.

• Engage Certified Professionals: Work with trained technicians for complex tests.

• Integrate SCADA Systems: Advanced monitoring provides real-time performance analytics.

7. When to Replace or Upgrade a Fire Pump

If your fire pump consistently fails to meet performance benchmarks, consider upgrading or replacing it. Signs you may need a replacement include:

• Performance falls below 95% of original ratings.

• Frequent repairs or downtime.

• Outdated technology not compliant with modern NFPA 20 standards.

• Expansion of your facility’s fire protection requirements.
  
  

8. Conclusion

Regular fire pump testing is essential to ensure your system performs reliably during emergencies. By following NFPA 25 guidelines, conducting annual flow tests, and implementing a preventive maintenance program, you can maintain maximum efficiency and system readiness.

At Better Technology Group, we manufacture UL-listed, NFPA 20-compliant fire pumps and provide expert guidance on fire pump testing, installation, and maintenance. If you want your fire protection system to deliver optimal performance when it matters most, testing should never be overlooked.