Hi-Fog open type spray heads. Models 4S 1MC 8MB 1000, 5S 1MC 8MB 1000, and 5S 1MC 8MC 1000.

Common issues

• Spray nozzle blockage from scale, debris or corrosion affecting the mist pattern
• Accumulator/pump unit pressure loss or pump failure
• Section valve failing to open or close on demand (manual or actuated)
• High-pressure piping corrosion or leakage at joints
• Poor water quality/filtration causing nozzle fouling
• Loss of power or control signal to the release/detection panel

Inspection checklist

• Check accumulator/pump unit pressure and standby readiness
• Visual check of nozzles for corrosion, blockage or physical damage
• Function test of section valves, manual and remote release
• Check high-pressure piping and fittings for leaks or corrosion
• Test the detection and release panel/alarm function
• Check water supply/filter unit condition
• Confirm local application zone coverage matches the protected equipment layout
• Review the last system function/flow test records

Service intervals

Typical wear limits

Ranges are typical for this design class. Always confirm against the manufacturer documentation for your serial number.

Critical spares

• Spray nozzle sets, correct type per protected zone
• Section valve actuator/solenoid
• Filter elements for the water supply unit
• Pressure switches/transmitters for pump control
• Seals/gaskets for high-pressure piping joints

Safety

• High-pressure water mist system - do not work on pressurised piping without isolation
• Accidental discharge risk during testing - follow lockout procedure and warn personnel in the space
• Electrical hazard at the pump/control panel during servicing
• Slip hazard from test discharge water in the machinery space

Class survey

Deviation from order data: this record is filed under 'CO2 Fixed System', but the product description identifies it as a Marioff Hi-Fog OPEN TYPE local-application WATER MIST system - this entry addresses the actual water mist system, not a CO2 fixed gas system. Local application water mist protection for machinery spaces is surveyed under SOLAS II-2 with annual function tests and periodic (often multi-year) high-pressure piping/accumulator inspection; class typically requires nozzle inspection and system flow test records.