A reliable fire fighting system must always be ready to deliver water the moment an emergency strikes. The small but critical component that keeps it primed and pressurized is the jockey pump.
In water-based fire protection systems such as sprinkler and hydrant networks, maintaining the required pressure in the piping is essential. One of the components responsible for holding that pressure is the jockey pump, also known as a pressure maintenance pump.
Although a jockey pump is far smaller than the main fire pump, it plays a critical role in keeping the fire protection system pressurized during normal conditions and preventing unnecessary operation of the main fire pump. It is one of the quiet workhorses behind well-designed fire protection systems and MEP services that keep a building safe.
What Is a Jockey Pump?
A jockey pump is a small-capacity pump connected to a fire protection water piping system. Its primary function is to maintain system pressure and compensate for small pressure losses when there is no actual fire demand.
Minor pressure losses can occur due to:
- Small leakage from fittings or valves
- Temperature-related pressure variations
- Minor seepage
- Testing or maintenance activities
- Other small losses in the piping network
When the system pressure falls below the preset level, the jockey pump starts automatically and restores the pressure. Once the pressure reaches the required level, the pump stops. The jockey pump is therefore a pressure-maintenance device — not a replacement for the main fire pump.
Why Is a Jockey Pump Important?
The main fire pump is designed to provide a large quantity of water during an actual fire. It should not start every time there is a small pressure drop in the system.
Without a jockey pump, even a minor pressure loss could cause the main fire pump to start unnecessarily. Repeated starting and stopping can result in:
- Mechanical wear
- Electrical stress
- Increased maintenance
- Reduced equipment life
- Unnecessary water consumption
The jockey pump handles these minor pressure losses and keeps the main fire pump available for genuine fire demand. This kind of reliability is a core part of the wider safety protocols that protect a construction project and its future occupants.
In simple terms:
How Does a Jockey Pump Work?
The operation of a jockey pump is controlled by system pressure.
1. Normal Condition
The fire protection piping is filled with water and maintained at the required pressure. The jockey pump remains on standby in automatic mode.
2. Pressure Drops
A small pressure loss occurs because of leakage, temperature changes or another minor system condition.
3. Pressure Switch Detects the Drop
When pressure reaches the predetermined jockey pump start setting, the pressure switch sends a signal to the controller.
4. Jockey Pump Starts
The pump starts automatically and supplies a small quantity of water to the fire protection network.
5. Pressure Is Restored
The system pressure increases to the required level.
6. Jockey Pump Stops
Once the predetermined stop pressure is reached, the controller stops the jockey pump.
During an actual fire, the water demand is much greater than the jockey pump's capacity. The pressure therefore continues to fall, causing the main fire pump to start and provide the required fire-fighting flow.
Main Components of a Jockey Pump System
A typical jockey pump installation includes:
Jockey Pump
A small centrifugal pump designed primarily for maintaining system pressure.
Electric Motor
Drives the pump and receives its operating commands from the controller.
Jockey Pump Controller
Automatically starts and stops the pump based on pressure signals and provides operational and fault indications.
Pressure Switch
Detects changes in system pressure and initiates pump starting or stopping.
Pressure Gauge
Provides visual monitoring of system pressure during operation, inspection and testing.
Check Valve
Prevents reverse flow through the pump when it is stopped.
Isolation Valves
Allow equipment to be isolated during maintenance.
Suction and Discharge Piping
Connect the pump to the fire protection water supply and distribution network.
Jockey Pump vs. Main Fire Pump
| Feature | Jockey Pump | Main Fire Pump |
|---|---|---|
| Main function | Maintain pressure | Supply fire-fighting water |
| Capacity | Low | High |
| Normal condition | Maintains system pressure | Standby |
| Minor pressure loss | Handles it | Normally remains off |
| Fire condition | May start initially | Supplies required flow |
| Purpose | Pressure maintenance | Fire protection |
Both pumps are important, but their functions are different. Coordinating them correctly with the rest of the building services is exactly the kind of task explored in MEP-intensive construction projects.
Importance of Correct Pressure Settings
Correct pressure settings are essential for reliable operation. The fire protection system normally has separate pressure settings for:
- Jockey pump start
- Jockey pump stop
- Main fire pump start
The exact settings depend on the approved fire protection design, system characteristics, applicable standards and equipment manufacturer's recommendations.
Incorrect settings can result in:
- Frequent jockey pump cycling
- Failure to maintain pressure
- Unnecessary main pump operation
- Difficulty identifying actual system leakage
Therefore, pressure settings should be established and verified by competent fire protection professionals.
Jockey Pump Maintenance
Regular inspection and maintenance are essential because the jockey pump forms part of a life-safety system. Maintenance should follow the equipment manufacturer's recommendations, applicable fire protection standards and the facility's approved maintenance program.
Routine Inspection
Check regularly for:
- Correct system pressure
- Pump availability in automatic mode
- Water leakage
- Unusual noise
- Excessive vibration
- Motor overheating
- Controller alarms
- Correct valve positions
- Electrical power availability
- Corrosion or physical damage
Functional Testing
Periodic testing should confirm that the pump responds correctly to pressure changes. Important checks include:
Automatic Start
Reduce system pressure to the approved start setting and verify that the jockey pump starts automatically.
Pressure Recovery
Confirm that the pump restores system pressure as intended.
Automatic Stop
Verify that the pump stops at the approved stop setting.
Pressure Switch
Check that the pressure switch operates correctly.
Controller
Verify power, running, fault and automatic operating indications.
The testing frequency should be based on applicable standards, manufacturer's recommendations and the facility's fire protection maintenance program.
Common Jockey Pump Problems
Frequent Starting
If the jockey pump starts repeatedly, possible causes include:
- Leakage in the fire protection system
- Faulty check valve
- Incorrect pressure settings
- Pressure switch problems
- Leakage from underground piping
Frequent cycling should be investigated rather than considered normal.
Pump Does Not Start
Possible causes include:
- Electrical power failure
- Controller not in automatic mode
- Faulty pressure switch
- Motor or control circuit problem
- Incorrect pressure setting
Pump Runs but Cannot Build Pressure
Possible causes include:
- Pump wear
- Air in the system
- Suction restriction
- Incorrect rotation
- Valve problems
- Check valve failure
- Excessive system leakage
Excessive Noise or Vibration
Possible causes include:
- Bearing problems
- Misalignment
- Cavitation
- Loose foundation
- Coupling problems
- Pipe strain
Any abnormal condition should be investigated by qualified personnel.
Best Practices for Jockey Pump Operation
For reliable operation:
- Keep the pump in automatic mode as required for normal operation.
- Monitor system pressure regularly.
- Investigate frequent pump cycling to identify possible leakage or control problems.
- Keep valves in their designated operating positions.
- Test pressure switches and controllers periodically.
- Inspect the pump and motor for leakage, vibration and overheating.
- Follow the manufacturer's maintenance instructions.
- Maintain inspection and testing records.
Good maintenance records can also help identify recurring problems before they become serious.
Frequently Asked Questions
What is the main purpose of a jockey pump?
Its main purpose is to maintain the required pressure in a fire protection piping network and compensate for small pressure losses, so the main fire pump does not have to start for minor drops. It keeps the system primed and ready.
How is a jockey pump different from the main fire pump?
A jockey pump is a small, low-capacity pump used only to hold system pressure. The main fire pump is a large, high-capacity pump that delivers the actual fire-fighting flow when there is a genuine fire. The jockey pump handles routine pressure maintenance; the main pump handles emergencies.
Why does my jockey pump start too frequently?
Frequent cycling usually points to a leak in the system, a faulty check valve, incorrect pressure settings, or a pressure switch problem. It should always be investigated rather than accepted as normal, because it can indicate hidden leakage or a developing fault.
Conclusion
The jockey pump may be small compared with the main fire pump, but its role in maintaining fire protection system reliability is significant. Its primary purpose is to maintain system pressure, compensate for minor pressure losses and prevent unnecessary operation of the main fire pump.
During normal conditions, the jockey pump keeps the fire protection network pressurized and ready. During a genuine fire event, when water demand becomes significant, the main fire pump takes over to provide the required fire-fighting flow. Proper selection, installation, pressure settings, testing and preventive maintenance are therefore essential for dependable performance.
The jockey pump does not fight the fire — it keeps the fire fighting system ready to fight the fire when it matters most.
