To Prevent DBL
Actually, this is a very special one of all of ECAM procedures.
It can be triggered only when ENG BLEED FAULT precedure for the opposite engine has been carried out, which result in (engine 1, for example):
- Engine BLEED 1: OFF
- XBLEED valve: OPEN
- PACK 1 & 2: both LO
Then comes this ENG BLEED HI TEMP procedure. When the temperature reach 240℃, quite near the threhold value 257℃ which would triggered a ENG BLEED FAULT alert and DBL (Dual Bleed Loss), FWC inform pilots to reduce bleed usage:
- PACK 2: OFF
Compared with the former "PACK 1 & 2: both LO" situation, will the remaining BLEED 2 feel cooler? YES!
BTW, you should read "A320 Family / A330 Prevention and Handling of Dual Bleed Loss" in Safety first #13 January 2012 for this issue.