A jockey pump is a small pump connected to a fire sprinkler system in order to maintain a certain pressure in the sprinkler system, and sized to ensure that if a fire-sprinkler is activated, there will be a system pressure drop.

A jockey pump is a small pump connected to a fire sprinkler system to maintain pressure in the sprinkler pipes. This is to ensure that if a fire-sprinkler is activated, there will be a pressure drop, which will be sensed by the fire pumps automatic controller, which will cause the fire pump to start.

A jockey pump is sized for a flow less than the flow to one sprinkler in order to ensure a system pressure drop. Hence a jockey pump is an important part of the fire pumps control system.

Jockey pumps are typically small multistage centrifugal pumps, and do not have to be listed or certified for fire system application. The control equipment for jockey pumps may however carry approvals.