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Flashcards in Pneumatics and air conditioning Deck (20):
1

In auto what controls compartment temperature?

The lowest compartment temp. Other compartments will use trim air to increase temp .

2

In standby what temperature is N C W

N 75.
C65
W 85 F

3

When pack has failed off how do you get back on.

Push reset

4

If inop light on what does the pack do?

Temp valve fails in the last position and pack works in a degraded mode.

5

When does high flow come on in pack.

When on the ground with external air
When in the air when one pack off or recirc off

6

What happens when the high stage light come on.

HP valve closes .requires maintenance action.

7

What happens with a bleed light on?

Bleed valve closes due high temp.
Can be reset by pushing bleed off then on if temperature reduced

8

Reason for isolation valve light on?

Fails to open or close to commanded position.

9

What happens when a recirc fan fails or is switched off?

The corresponding pack will go to high flow.

10

Where is the air go to from the recirc fans.

To the mix manifold

11

How many equipment cooling fans are there and how many work at the same time.?

3 fans
Supply
Alternate
Auxiliary
Only 1 operates at one time.

12

When does the overboard exhaust valve from the Eand E bay open and close.

When diff is 2.5 psi

13

What happens to the overboard exhaust valve when the left pack fails.

It opens and provides circulation due to differential pressure

14

How many fans in aft equipment and how many work at once.

2 fans only one works at a time other is automatically switched on if other fails.

15

Equipment cooling overheat light on when.

Supply fan inop,alternate fan inop ,exhaust duct failed, recirc fan inop.
Basically when no circulation due to above.

16

If equipment cooling o/h light remains on after selecting to alternate .what is most likely cause?

Both aft equipment fans have failed.

17

Smoke in left recirc duct causes?

Left recirc fan to switch off
O/B exhaust valve opens
Left pack goes to high flow.

18

Smoke in the supply duct causes what?

Both recirc fans off
Both packs to high flow
Supply fans turned off.

19

What is the temperature range of the packs in auto

18 to 30 c

20

How many zones in cabin.

Felt deck
Forward
Aft
3 all up .