Test rig
Use either a flowmeter on a test loop (preferred) or test header with calibrated hose-stream nozzles. Pitot readings convert to flow with Q = 29.84·c·d²·√P.
Three test points
1) Churn (zero flow): head ≤ 140% of rated. 2) Rated flow: head = 100% of rated. 3) 150% flow (overload): head ≥ 65% of rated. All three must fall on or above the certified curve.
Common failures
Drop > 5% from previous year curve usually means worn impeller, eroded volute, or supply degradation. Diesel pumps add cooling water, fuel, and battery checks. Electric pumps log start signal time, transfer switch, and motor current.
Documentation
NFPA 25 §8.3.7 requires the test record, with all three points plotted vs the original certified curve, retained for the pump's life. Insurance auditors look for this first.
Quellen
- NFPA 20 (2022) §14.2
- NFPA 25 (2023) §8.3
Cite this page
- APA
- FireTwin AI (2026). Fire pump testing — churn, rated and 150% (NFPA 20). FireTwin AI. https://firetwin.eu/de/learn/pump-test
- IEEE
- FireTwin AI, "Fire pump testing — churn, rated and 150% (NFPA 20)," FireTwin AI, 2026. [Online]. Available: https://firetwin.eu/de/learn/pump-test