Fire pump testing: weekly and monthly runs, and the annual flow test
Updated November 2026 · Bruhn & Bruhn Fire Protection
A fire pump is run on a routine schedule without flowing water (weekly for diesel, and monthly for most electric pumps), and once a year it's flow tested at no flow, at its rated capacity and at 150% of it, with the results compared against the pump's original curve.
The routine runs
NFPA 25 has the pump started and run without flowing water on a fixed schedule, so problems show up long before a fire does: diesel pumps every week for at least 30 minutes, and electric pumps every month for at least 10 minutes (more often in some buildings, such as high-rises). During each run someone records the suction and discharge pressure, checks the packing glands and the pump room, and, on a diesel, the engine's temperatures and oil pressure.
Many pumps run these tests on an automatic timer. Someone still has to be there to watch and record the run.
The annual flow test
We flow water through a test header or a flow meter, take the readings at each point, and plot them against the pump's original performance curve. A pump that has dropped more than about 5% below its curve, adjusted for speed, needs investigating: worn impellers, a partly closed valve, or a weaker water supply than the system was designed for.
The same visit tests the controller and the alarms it sends, the automatic transfer switch where there's one, and the diesel's battery and fuel system.
| What | How often |
|---|---|
| No flow (churn) | Pressures and speed with no water flowing |
| 100% of rated flow | Pressures, flow, speed, and for electric pumps voltage and current |
| 150% of rated flow | The same readings at peak flow |
| Comparison | Results plotted against the manufacturer's curve and the acceptance test |
When we're called
We do the annual flow test and show building staff what to watch on the routine runs. We also come out when a pump won't start, runs on its own, or a test result looks wrong, and we install and replace fire pumps and controllers when a building's needs change.
Frequencies here follow NFPA 25, 2023 edition. Your fire marshal or insurer may enforce a different edition or add requirements of their own; we'll tell you which applies to your building.
Questions owners ask
- How often does a fire pump need to be tested?
- Under NFPA 25, diesel fire pumps run without flow every week and most electric fire pumps every month, and every fire pump gets a full flow test once a year.
- What happens if the fire pump fails its annual test?
- We find out why, whether it's the pump, a valve, the driver or the water supply, and quote the repair. If the pump can't deliver the water the sprinklers need, it's treated as an impairment and the fire marshal and insurer may need to be told.
Want us to handle it?
We do this work for commercial buildings across Middle Tennessee, North Alabama and Kentucky. See our fire pumps service, or ask for a quote.