FCOM 06 JUN 12
AIB A318/A319/A320/A321 FLEET
DSC-36-10-30 P 1/2
DESCRIPTION - APU BLEED AIR SUPPLY
GENERAL
Applicable to: ALL
The APU bleed valve operates as a shut-off valve to control APU bleed air. It is electrically-controlled and operated by fuel pressure*.
The APU BLEED pb-sw, on the AIR COND panel, controls the APU bleed valve. When the flight crew selects ON with the pushbutton, APU bleed air supplies the pneumatic system, if the APU speed is above 95 %. This opens the crossbleed valve and closes the engine bleed automatically. A check valve near the crossbleed duct protects the APU, when bleed air comes from another source.
(The text in blue above was introduced in FCOM after we installed Ham Sund APS320 APU. For the Honeywell APU the text would read pneumatically controlled. I think the intent in saying it is operated by fuel pressure is that it implies N>95% before the valve can open )
Last edited by nnc0; 1st Jul 2012 at 12:11.