Equipment cooling

Question 1

For what compartment/system does the equipment cooling provide cooling air?

Answer 1

Electrical and Electronic (E&E) compartment

Question 2

When is warm equipment cooling air ducted overboard on the ground?

Answer 2

• engines not running
• ambient temps moderate or high

Question 3

When does the equipment cooling system configure for flight?

Answer 3

• engines not running + lower ambient temps (on ground) or
  
- one/more engine on each wing operating (on ground) or
  
- LLCAFR in OFF, FWD LOW, BOTH LOW, FWD HIGH and temp selected 10 deg and higher or
  
- STBY selected - auto control bypassed to configure system for flight

Question 4

How can you manually configure the equipment cooling system for flight?

Answer 4

• STBY selected - auto control bypassed to configure system for flight

Question 5

Which valve is closed when equipment cooling is in closed loop mode?

Answer 5

INBD exhaust valve

Equipment supply valve

Question 6

What is the source of equipment cooling air for the flight deck?

Answer 6

Flight deck equipment cooling source valve
With 2 or 3 packs operating, directs conditioned air to FD elec equipment

Question 7

Describe the operation of the equipment cooling system with the Equipment Cooling Selector in OVRD.

Answer 7

INBD exhaust valve closed

Ground exhaust valve closed

Equipment supply valve closed

Smoke/ovrd valve open

cooling air supplied through flight panels

differential pressure exhausts cooling air overboard (reverse airflow
)