NFPA 25 requires that fire pumps be tested at regular monthly and annual intervals. This helps to verify that the system is operating effectively. These inspections and testing procedures should be performed by a C16 Licensed Professional.
What is a fire pump?
Fire pumps play a crucial role in a building's fire safety setup, particularly in taller structures such as high-rise buildings with levels exceeding 400-500 feet. They are essential for ensuring adequate water pressure to disperse water throughout sprinkler systems, especially when the pressure from water mains and firefighting equipment is insufficient. While fire pumps are particularly critical in taller buildings, they remain an important element in fire protection for all buildings.
As a building owner or facilities manager, it is your legal obligation to maintain and ensure the proper operation of the equipment supplying your sprinkler system, especially if it involves a fire pump. If you lack the expertise or time to do so, it is necessary to engage the services of a qualified professional. However, beyond legal compliance, maintaining your equipment is a worthwhile endeavor given the undeniable significance of your sprinkler system. In the unfortunate event of a fire, a functioning sprinkler system can make all the difference in saving both property and lives.
What are the types of fire pumps?
Fire pumps typically fall into two categories: those driven by electric motors and those powered by diesel engines. Depending on the type of fire pump installed in your building, the recommended testing methods and frequency may differ. For electric motor-driven fire pumps, it is advisable to conduct a visual inspection by operating the equipment for at least ten (10) minutes once a week.
It is not necessary to measure water flow during this test, but it is important to have a qualified individual present to attend to any issues that may arise. Although NFPA 25 allows for monthly testing under certain circumstances, we strongly suggest a weekly test due to the critical nature of the equipment.
How to test a fire pump
- To ensure the fire pump starts automatically, it's crucial to simulate a pressure drop in the system. This test will detect any malfunctions with the pressure switch or transducer, and it's best to identify them promptly.
- To maintain proper functioning of the pump, it's essential to control the packing drip. During operation, some water flow through the pump's packing boxes is normal, but excessive water splash is not. Adjust the packing glands as needed to keep the water flow constant and low by a quarter turn. After the equipment has been turned off, the packing should leak at around one (1) drip per second. Tightening the packing to the point of zero drip is not advisable, as it can lead to dryness of the packing, reduce its effectiveness, damage the shaft sleeve, and shorten the packing's lifespan.
- To prevent the pump casing from overheating, ensure that the casing relief valve (also called the circulation relief valve) is allowing enough water to flow and that it shuts off when the pump is turned off. The water temperature should be warm to the touch, but not excessively hot. Some adjustment may be necessary.
- Verify that the packing drip drains are clear of sediment or debris.
- Keeping a log of your testing is recommended as it will provide useful information to your insurance company if needed and help you stay on schedule.
Notes on Diesel Fire Pumps
To ensure the diesel-driven fire pump's proper functioning (assuming standard water-cooled engines), you need to run the equipment weekly. This helps the engine's smooth operation by heating up the engine block and utilizing some fuel. Over time, diesel fuel can deteriorate, and it's advisable to avoid using old fuel in the diesel-driven engine. Ideally, it would be best to consume the fuel before it exceeds two years of age.
The checklist above should also be used for testing diesel pumps. However, the casing relief valve mentioned in point #3 for electric pumps is substituted with a water cooling loop for diesel pumps.
It is crucial to ensure that water is flowing through this loop since it not only cools the pump casing, but also the internal engine cooling loop. It is essential to maintain the water flows within the recommended range provided by the engine and pump manufacturer.
To ensure the fire pump works correctly, there are additional points to consider:
- Diesel Fire Pumps require Weekly Testing. That is a big responsibility and something you should not fail to remember!
- Keep the strainers on the water cooling loop clean after running the engine and check that the engine exhaust and room ventilation are functioning correctly.
- It is also important to verify that the batteries are in good condition and that the fire pump sends an "engine running" signal to a monitoring point if the pump room is not continuously supervised.
- It is essential to ensure that if the engine starts, someone will be alerted immediately.
Regularly running your fire pump equipment and keeping a written log of the results is crucial in preventing a minor issue from turning into a catastrophic event. Fire pumps often sit in remote locations and remain off for extended periods. The only way to keep track of the equipment's condition is by regularly starting and observing its operation as per the schedule outlined in NFPA 25.
We hope this guide helped you understand not just the testing frequency of fire pumps, but the importance of doing so. If you are in need of testing for your fire sprinkler system (we do it all), get a free estimate from Legion Fire Protection when you call or email us today!