We’re currently operating a GE 7FA.03 turbine, primarily running on natural gas. However, during liquid fuel switchover, we’ve been experiencing frequent trips. The trips usually happen within the first 15 minutes of liquid fuel operation.
Here’s what we’ve observed:
Alarms triggered: L60LF1 (Liquid Fuel Trip) and L83FLP (Fuel Pump Low Pressure).
Liquid fuel pump pressures drop sharply before the trip.
Liquid fuel forwarding skid has been inspected, and there were no apparent mechanical issues.
We’ve confirmed no air entrainment in the fuel lines.
Water content in the fuel is within spec.
Our concern is that we may have a deeper issue in the liquid fuel control valve (LFBV) or the liquid fuel purge system. Has anyone encountered similar issues? What troubleshooting steps do you recommend?
The L60LF1 alarm is generally tied to low fuel pressure or anomalies in the liquid fuel control valve (LFBV). I’ve seen cases where the LFBV servo was out of calibration, causing erratic fuel flow during switchover. Have you checked the servo calibration recently? I’d recommend a full servo loop check during your next downtime.
The L83FLP alarm indicates a fuel pump pressure drop. Since you’ve ruled out mechanical issues with the pump, I’d look at the purge air system. If the purge air valve is leaking, it could cause pressure drops during switchover. Check your purge air valves and make sure they are fully seating.