We get calls every year from property managers who just failed an AHJ inspection — not because their sprinkler system was bad, but because nobody had touched the fire pump in three years. The sprinkler inspection was done. The tags were current. But the pump? Forgotten.
That’s a problem, because without a working fire pump, your sprinkler system might not have enough pressure to do anything when it actually matters.
The pump is not part of your sprinkler inspection
This is the part that catches people off guard. NFPA 25 covers fire pumps under Chapter 8 — completely separate from the sprinkler inspection. Your sprinkler contractor can show up, do a full annual inspection, hand you a clean report, and never touch the pump room. Both parties leave thinking they’re done. Then your insurance auditor or AHJ asks for pump test documentation and you’ve got nothing.
If you’re not sure whether your pump has been tested separately, check your paperwork. Look for a flow test report — not just a visual check, but an actual document showing churn pressure, 100% flow, and 150% flow plotted against the pump curve. If you don’t have that, it probably hasn’t been done right.
What the testing actually involves
For weekly churn tests, a technician runs the pump at no-flow conditions for at least 10 minutes. It confirms the pump auto-starts when it’s supposed to and runs without issues. Most buildings are supposed to be doing this every week — in reality, a lot aren’t.
The annual flow test is the one that really counts for compliance. We hook up a flow meter, put pressure gauges on the suction and discharge, and run the pump through three conditions: churn, rated flow, and 150% of rated flow. The results get plotted against the factory performance curve. If the numbers are where they should be, you get a passing test report. If they’ve drifted, we flag it.
Diesel pumps take longer — figure an extra hour or two on top of what an electric pump takes, because we’re also checking the fuel system, batteries, exhaust, and controller functions. A building with multiple pumps or a jockey pump setup should plan for a half-day.
What we see when pumps fail
The most common issue we find is performance that’s dropped off the factory curve. The pump starts, it flows — but the pressure numbers are low. Usually that’s impeller wear, a valve that got bumped partially closed, or corrosion inside the casing. Sometimes it’s still within a compliant range with a noted deficiency. Other times it needs repair before we can sign off.
Failure to start is worse. If the pump doesn’t kick on automatically when pressure drops to the start point, that’s a critical deficiency. The system goes on fire watch immediately, you notify your AHJ and insurance carrier, and the pump doesn’t go back into service until the controller or pressure sensing issue is fixed. Most commercial policies give you 24 to 48 hours to make that call — don’t sit on it.
On diesel pumps, the failures we see most often come from pumps that just sit there between tests. Batteries weaken, fuel degrades, exhaust joints corrode. This is exactly why the weekly churn requirement exists. Buildings that actually run weekly tests catch these things early instead of at the annual flow test.
Altitude matters more than people think
Denver is at 5,280 feet. Boulder and Fort Collins are higher. Cheyenne is over 6,000 feet. Pumps are rated at sea level, and that rating doesn’t automatically translate to altitude — especially for diesel-driven units where lower atmospheric pressure reduces engine output.
If your building has an older pump and the performance curve on file with your AHJ is the original sea-level document, it’s worth a conversation with your service contractor. You might be testing against a curve your pump was never going to hit at this elevation. We see this more than you’d expect on buildings that were installed with out-of-state specs.
If you don’t have recent documentation
Schedule the annual flow test before your next insurance renewal or AHJ walk-through. Missing pump test records are one of the most consistent findings we run into during NFPA 25 inspections across Denver, Aurora, Boulder, Fort Collins, and Cheyenne — and it’s one of the easier things to get ahead of before it becomes a problem.
We do fire pump testing and repairs across the Front Range and into Wyoming. If you want to get on the schedule or have questions about what your building needs, give us a call at (720) 382-9669.