A320 Air Conditioning

Front 1

What is the mixing unit connected to?

Back 1

3 cabin zones, PACKS, Ram air inlet valve, low pressure ground air

Front 2

What controls the PACK?

Back 2

ACSC and PACK controller

Front 3

What is the purpose of the ram air inlet valve?

Back 3

Allow ram air into the mixing unit in the event both PACKS fail or smoke removal is required

Front 4

When does the hot air pressure regulating valve close automatically?

Back 4

Duct overheat

Cockpit trim air valve failure

Both cabin trim air valves fail

Both lanes of an ACSC fail

Front 5

What controls the 3 trim air valves?

Back 5

Zone controller or ACSC

Front 6

What sends signals to the PACKS to control output temperature?

Back 6

Zone controllers or ACSC

Front 7

How many zone controllers are there?

Back 7

2

Front 8

Describe the Ram Air Inlet Flap

Back 8

Opens to decrease pack output temperature

Closed during takeoff and landing to prevent FOD ingestion

Front 9

What are the criteria for ram air inlet flap operation?

Back 9

Takeoff - closes when takeoff thrust applied and struts compressed

Landing - closes when the struts compress and speed above 70kts.

Landing - opens 20 seconds after speed drops below 70kts

Front 10

What happens if any one zone temperature demand cannot be satisfied when the APU bleed is open?

Back 10

ACSC signals the APU Electronic Control Box (ECB) to increase APU flow output

Front 11

What happens if cooling demand of any one zone cannot be satisfied or bleed pressure is too low?

Back 11

ACSC sends a pressure demand signal to both Engine Interface Units (EIUs) to increase the minimum engine idle

Front 12

Describe PACK controller primary channel failure

Back 12

Regulation not optimized

PACK flow fixed at previous setting

Front 13

Describe PACK controller secondary channel failure

Back 13

Back up mode lost

ECAM signals lost

No effect on PACK regulation

Front 14

Describe PACK controller dual channel failure

Back 14

PACK outlet temperature controlled by anti-ice valve

Temperature between 5-30 degrees (max 6 minutes)

ECAM signals lost

Front 15

Describe zone controller primary channel failure

Back 15

Flow settings & temperature regulation lost

Hot air & trim air valve closes

Zones set to 24°

PACK 1 controls cockpit

PACK 2 controls FWD/AFT cabins

ALTN mode on ECAM

Front 16

Describe Zone Controller secondary channel failure

Back 16

Backup mode lost

No effect on zone temperature regulation

Front 17

Describe zone controller dual channel failure

Back 17

Optimized and backup temperature lost

PACK 1 20°C

PACK 2 10°C

ECAM COND page info removed

PACK REG on ECAM

Front 18

Describe Air Cycle Machine failure

Back 18

PACK operates in heat exchanger cooling mode

Air cooled by the heat exchanger goes through the bypass valve and failed ACM

ACSC regulates temperature by modulating ram air inlet flap and bypass valve

PACK flow is reduced and hot air flow is reduced

Front 19

Describe Hot Air Pressure Regulating Valve failure

Back 19

Failed Open - No Effect

Failed closed:

Optimized regulation lost

Trim air valves close

PACK 1 controls CKPT to selected value

PACK 2 controls FWD & AFT to the mean value of selected temperatures

Front 20

Describe trim air valve failure

Back 20

Optimized regulation lost for the respective zone

Front 21

What are the corresponding temperatures to the zone temperature control knob?

Back 21

Cold 18°

12 o' clock 24°

Hot 30°

Front 22

FAULT light on Hot Air pushbutton (ECAM caution)

Back 22

Duct temp reaches 88°C once

HAPRV and all trim air valves close automatically

Light goes out when temp drops below 70°C and flight crew selects off

Front 23

FAULT on PACK pushbutton (ECAM caution)

Back 23

PACK flow control valve disagrees with selected position

Compressor outlet overheat

PACK outlet overheat

Front 24

Describe the 3 positions of the PACK flow knob

Back 24

Lo - 80% (less than 141 pax)

NORM - 100%

HI - 120% (abnormally hot or humid)

Front 25

When does the PACK use HI Flow?

Back 25

Single PACK operation

APU supplying bleed air

(Ignores PACK FLOW selector)

Front 26

Describe the Ram Air pushbutton

Back 26

Normally controlled automatically

Manual - pushbutton opens the Ram Air valve if ditching not selected and Delta P < 1psi

Front 27

Describe the CAB FANS pushbutton

Back 27

Dark - both recirculation fans enabled.

Filtered cabin air ducted into the mixing unit

OFF - switch selected off and both fans off

Front 28

How is zone controller failure indicated on ECAM COND page?

Back 28

ALTN MODE - Primary Zone Controller fault

PACK REG - Dual Zone Controller fault

Front 29

On ECAM COND page describe HAPRV indication

Back 29

Inline green - normal open

Inline amber - abnormal open

Crossline green - normally fully closed

Crossline amber - closed and pushbutton set off, or valve disagrees with control position

Front 30

On ECAM BLEED page, describe the amber indication of ram air inlet flap

Back 30

Amber inline - Ram air inlet fully open on ground

Amber variable - Ram air inlet flap in transit

Front 31

Describe the PACK bypass valve indication on the ECAM BLEED page.

Back 31

C - Fully closed

H - Open

Front 32

When does the PACK flow indicator become amber on ECAM BLEED page?

Back 32

PACK flow control valve is closed

Front 33

How different can the PACK flow indicator be from the actual rate?

Back 33

30% below

Front 34

What is indicated by an Amber PACK 1 or 2 on ECAM CAB PRESS page?

Back 34

PACK flow control valve closed while associated engine running

Front 35

Can HP ground air be used for air conditioning?

Back 35

Yes

Do not use APU to simultaneously provide bleed air

Air supply must be confirmed free from oil contamination

Front 36

What is the caution when using LP bleed air?

Back 36

Do not operate PACKs with any HP bleed air source

Front 37

When does the PACK Flow Control Valve close automatically?

Back 37

Pack overheat (ground)

Engine start

Fire Pushbutton

Ditching Pushbutton

Front 38

What happens to the outflow valve when the RAM AIR pushbutton is ON?

Back 38

If under automatic control:

Opens to about 50% if delta P is less than 1 PSI and ditching not selected

Front 39

When the Ram Air pushbutton is selected ON, when does the Ram Air Door open?

Back 39

If ditching is not selected

Front 40

Which ACSC controls the Hot Air Pressure Regulating Valve?

Back 40

ACSC 1

Front 41

Which ACSCs control the trim air valves?

Back 41

ACSC 1: cockpit

ACSC 2: cabin

Front 42

Where is the actual air temperature measured inside the aircraft?

Back 42

Cockpit: cockpit

Cabin: lavatory extraction circuit and galley ventilation system

Front 43

Describe basic temperature regulation

Back 43

Signal corresponding to the lowest zone goes to the pack controller or ACSC which makes both packs supply that temperature

Front 44

Describe optimized temperature regulation

Back 44

Zone controller or ACSC controls the trim air valves to maintain temperature between 18-30 degrees C

Front 45

How does the ACSC regulate the temperature of its associated PACK?

Back 45

Modulating the ram air inlet flap and bypass valve

Front 46

How does an ACSC regulate flow of its respective PACK?

Back 46

Modulating the associated PACK Flow Control Valve

Front 47

What happens if the flight crew selects LO pack flow and the temperature demand cannot be satisfied?

Back 47

The system supplies normal flow

Front 48

Describe normal PACK flow on the ground with both engines running on A320 NEO

Back 48

It’s limited to 90%

Front 49

Describe ACSC lane failures

Back 49

1 lane: other lane takes over

2 lanes: related PACK lost, hot air pressure regulating valve and all trim air valves close

Front 50

Describe the positions of the HOT AIR pushbutton

Back 50

ON: valve regulates hot air pressure

OFF: valve closes and trim air valves close. Fault circuit reset

Front 51

When does the pack flow control valve automatically close?

Back 51

Upstream pressure below minimum

Compressor outlet overheat

Engine start sequence

FIRE pb of the engine on related side pushed

Ditching selected

Front 52

Describe pack flow control valve operation during engine start (CEO)

Back 52

Valve on engine start side (both if crossbleed valve open) closes when mode selector set to IGN or CRK

Remains closed if:

-MASTER sw is ON (or MAN START pb)

-Start valve open

-N2 less than 50%

On ground, reopening of valves delayed 30 seconds to avoid pack closure during second engine start

Front 53

Describe pack flow control valve operation during engine start (NEO)

Back 53

Valve on engine start side (both if crossbleed valve open) closes when mode selector set to IGN or CRK

Remains closed if:

-MASTER sw is ON (or MAN START pb)

-Start valve open

-N2 less than 50%

On ground, reopening of valves delayed 60 seconds to avoid pack closure during second engine start

Front 54

When does PACKS appear on the Engine Warning Display for the A320 NEO?

Back 54

When the thrust levers are in theTOGA or FLX/MCT detent.