Chapter 3: Fault finding – ECU faults
20
ZP3-ECU Extinguishing Control Unit Maintenance Manual
Extinguishant pressure faults
Indications
• The Extinguishant Pressure Low LED on the ECU main board illuminates
• The Fault LED on the ECU front panel illuminates.
• A GNFLT fault message is displayed on the fire alarm control panel and the
panel buzzer sounds. The Fault LED on the fire alarm control panel also
illuminates.
GNFLT Zone 001 Dev 5001 Event 002
Possible causes
• The EOL resistor across the Extinguishant Pressure Low switch is not
inserted.
• The extinguishant pressure is low.
Corrective actions
1. Press the Accept button to acknowledge the fault.
2. Inspect the EOL resistor. If missing, insert one between terminals 17 and 18
of TB1 and the ECU main board.
3. Reset the panel.
4. If the condition still exists, check the pressure in the extinguishant cylinder.
