- Sketch a line diagram of an automatic sprinkler system, labelling the MAIN components.
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Automatic Sprinkler System – Line Diagram & Description
Main Components to Show in the Line Diagram:
- Freshwater tank / pump supply – initial water source for system.
- Fire pumps –
- Main fire pump (supplies system under emergency).
- Jockey/maintenance pump (keeps system pressurised under standby).
- Emergency pump (often diesel-driven, independent).
- Control valves – isolation and alarm valves for each sprinkler section/zone.
- Distribution piping – branch lines running through protected spaces.
- Sprinkler heads – fitted in overhead piping, individually heat-activated.
- Alarm system connection – flow/pressure switches to trigger alarm when water discharges.
- Drain/test line – for system testing and maintenance.
Line Diagram (exam-style)
Draw a left-to-right or top-to-bottom schematic:
- Water supply (tank/sea connection) → Jockey Pump (standby) + Main Fire Pump + Emergency Diesel Pump → Control Valve/Alarm Valve → Distribution Piping → Sprinkler Heads (with deflector plates shown).
- Show Alarm Switch connected to the control valve (activates alarm when flow detected).
- Add Drain/Test Line branching from distribution line.
How it works (summary for examiner):
- System is kept under pressure by the jockey pump.
- When a sprinkler head opens (due to fire heat), water discharges.
- Pressure drop starts fire pumps automatically and activates the alarm system.
- Water is sprayed directly onto the fire via the opened heads only.
✅ Marking (10 marks):
- Correct flow sequence (3).
- Pumps and supply (2).
- Control/Alarm valves (2).
- Sprinkler heads shown (2).
- Drain/test line (1).