Fuel L Wing Tk Overflow

[yamaha]

Can anyone explain the potential consequences of this A320 fault message

[yamaha]

Smudgethecat, Do you know that would be a potential consequence or were you speculating?

[františek dobrota]

This ECAM message is from A321 only.(Maybe I am wrong)

Tech. doc. quote:
During aircraft operations on the ground and in flight, it is possible for fuel to get into the vent/surge-tank. If this occurs during normal (serviceable) operation the clack valves let the fuel move back into the related wing-tank.

If the two clack valves 214QM and 216QM become unserviceable, in the closed position, fuel can collect in the related vent/surge-tank. The collected fuel quantity will increase (cumulatively in separate, successive additions) until the status of the related sensor 28QJ1 changes from dry to wet.

This can cause the two related results that follow:

- the ECAM warning 'FUEL L WING TK OVERFLOW' will be given, if in an applicable flight phase


- the P/BSW-FUEL/CTR TK/L XFR (5QL) FAULT legend will light, if it was set to the on (pushed in) position.


NOTE:
The FAULT legend of the P/BSW-5QL can come on in the AUTO or the MAN (fuel transfer) configuration.

In the left wing it can also cause the fuel level to increase until it is above the level of the center-tank vent (duct/outlet-pipe at RIB22). Gravity can then cause fuel flow through the center-tank vent and into the center tank.
Possible Causes
- CLACK VALVE (214QM)


- CLACK VALVE (216QM)


- SDAC-1 (1WV1)


- SDAC-2 (1WV2)


- Transfer Control Valve 1 (Left) does not close


- Main Transfer System Auto Control Failure









So consequence is - on ground fuel leak from NACA inlet, if transfer or refueling not stopped or fuel leak and center tank fuel loss inflight with transfer still running.