In the Airbus A320 FCOM in some places "LP fuel valve" is mentioned (in Fire and Fuel System chapters) whereas in the engine chapter "LP fuel Shut off valve" is mentioned.

Is there any difference between the two?


2 Answers 2


The "LP fuel valve" and "LP fuel Shut off valve" are the same valve just being named differently in different sections of the FCOM.

The valve is located in the wing leading edge and is also sometimes referred to as “spar valve” by engineers who also work on Boeing aircraft.

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  • $\begingroup$ Somebody in the Airbus Pubs department isn't following Airbus's Nomenclature standard. $\endgroup$
    – John K
    Commented Mar 12, 2021 at 21:22

They are the same valve.

The engine has two fuel (shut off) valves:

  • LP valve: This valve is located in the leading edge of the wing and can stop any fuel flowing towards the engine through the pylon. When it is closed (e.g. by the fire handle), the entire engine with all of its systems is starved of fuel.
  • HP valve: This valve is located deep within the actual engine. It controls the fuel going to the combustion chamber. It is opened by the FADEC during normal engine start. But even when it is closed, the engine still receives fuel for all the other systems (see diagram below).

This is the engine fuel diagram from the FCOM:

Engine Fuel
(Airbus A320 FCOM - Power Plant - Fuel System)

As you can see, the LP valve is right at the beginning of the fuel flow diagram. The cold fuel is used for cooling the engine oil (fuel oil heat exchanger and servo fuel heater) and the Integrated Drive Generator (IDG oil cooling). It is also used for hydraulic control. The HP valve is shown at the bottom before the fuel metering unit and the engine fuel nozzles.


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