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Fire pumps are often a forgotten element of an automatic fire protection system.

A reliable fire water supply may be the most important component of properly designed fire protection system.

 Indeed without a reliable and adequate water supply, the remaining fire protection system is unpredictable and therefore puts property, occupants and fire responders at risk. Adequacy of a fire water supply can even impact costs as many insurers consider the fire water supply as one of the key defining qualities in rating a property risk.

Fire Pumps are usually powered by an electrical motor or they are a directly connected to a diesel engine, or in rare cases, a steam turbine. Fire Pumps are connected to a water storage tank or other water source and they become active when the pressure in the fire protection system drops.

 For example in a sprinkler system when one or more sprinkler heads are exposed to heat above their design temperature, the sprinkler head releases and water discharges, pressure drops and fire pumps start.

In order to maintain adequate water pressure in a fire protection system jockey pumps are used.

Jockey pumps become active when the water pressure inside the system dips below a lower

threshold than the fire pump's threshold. The jockey pump is sized so it will compensate for pressure losses from small leaks, expansion and evaporation. In a fire sprinkler system, the size jockey pump is kept under the demand of one sprinkler head so that the main fire pump will start when a sprinkler head is fused, 5 to 10 USGPM is generally acceptable. It should not exceed the water demand of one sprinkler, which is 20 USGPM.

Types Of Fire Pumps

Horizontal split case pumps

Horizontal split case double suction pumps

Vertical In-line centrifugal pumps

End suction single stage pumps

Centrifugal Fire Pumps Capacities

GPM : 25, 50, 100, 150, 200, 250, 300, 350, 400, 500, 750, 1000, 1500, 2000.

NFPA 20 states that "Pumps shall furnish not less than 150 percent of rated capacity at not less than 65 present of total rated head. The shutoff head shall not exceed 140 percent of rated head for any type pump".