How to Install a Diesel Fire Pump

A diesel fire pump is a crucial component of any fire protection system. They deliver high-pressure water to sprinklers when called upon, and are often located in a fire pump room that is required by NFPA 20 standards to be sprinklered and protected from damage or floods. Fire pumps are complex pieces of equipment, so it’s essential that they be maintained regularly to ensure optimal performance.

There are many factors that impact the performance of a fire pump, including head (pressure) and flow. Power consumption is also an important consideration. The best way to ensure that a fire pump is performing at its peak is to periodically perform a full-flow test. During the test, water is delivered through the nozzles at each station and the suction and discharge pressure readings are recorded to verify that the pump is working correctly.

During the test, it’s important that all the gauges used to measure the performance of the pump are accurate and calibrated. These gauges should be able to read within +/- 1 percent of the manufacturer’s specifications and be capable of recording trends over time. If standard gauges aren’t available, then other types of specialized equipment can be used to record the test data, such as tachometers or ammeters. During the test, it’s also important to wear protective gear, only use hoses that have passed a test and never hold any of the hose nozzles during a flow test. T-shaped hose monsters that counteract the force of the flowing water are safer to use during a test.

The piping for the diesel engine exhaust system is another vital part of the installation. It needs to be sized appropriately to prevent back pressure from building up and preventing the engine from producing power. The piping should be properly guarded and insulated to protect personnel from heat transfer and the temperature of the exhaust should be monitored.

A cooling water jacket can be installed for the diesel engine as a way to keep it running at the proper temperature. This is a great option for fire pumps that are operated in remote locations where the temperature can change significantly. A thermostatically controlled heater will be able to maintain the correct water jacket temperature during the fire pump test and help ensure reliable starts.

When the installation is complete, the fire pump must be tested to verify that it is functioning correctly and that it complies with NFPA 20 requirements. If any of the equipment doesn’t meet these requirements, it must be field corrected or replaced.

Recently, DXP Field Service Technicians helped a customer replace their Plant 1 diesel engines and install new double-wall Diesel Tanks and associated piping. This brought their Fire House up to code and eliminated the need for them to have to manually start their old engines. This saved the customer a lot of money and time, while still providing them with the best fire protection system for their facility.