A320 Air Conditioning Flashcards
What automatically controls the air conditioning system?
2 Air Conditioning System Controllers (ACSC’s)
What does ACSC stand for?
Air conditioning system controller
What valve controls the flow of air to the packs?
The “Pack Flow Control Valve”
How many channels do the ACSC’s have?
2
What would happen if an ACSC completely fails?
The Hot Air Pressure Regulating Valve and the associated Trim Air valves would close automatically
What happens to the pack flow control valves when the engine mode selector is selected to IGN/START?
The pack control valves close automatically to lessen the demand on the pneumatic system in preparation for engine start. If after a short time the engines are not started, the pack flow control valves will automatically open.
What could cause a pack flow control valve to close automatically?
-Engine mode selector selected to IGN/START
-ACSC dual channel failure
-ENG FIRE pushbutton selected on the overhead panel
-Selecting the DITCHING pushbutton to “ON” on the overhead CABIN PRESS panel
-A pack overheat
-Lack of airflow. The valves are spring loaded to the closed position and if there’s insufficient air flow they close automatically
What will happen on the ground if the packs are selected on, but neither engines or APU are running?
The fault light will illuminate on the PACK 1/2 push buttons. This is because neither the APU nor engines are on, thus there’s nothing to provide bleed air to the packs. This means there’s no airflow through the pack flow control valves. Because the valves are spring loaded to the closed position and only airflow keeps them open, the valves will remain closed even if the PACK pb’s are pushed. When the PACK push buttons are selected on, the plane will sense a disagreement between the command position (open) and the actual position (closed) of the pack flow control valves, which is communicated to the pilots through a FAULT light.
What does a fault light on #2 mean
A disagreement between the selected and actual position of the pack flow control valve, a pack outlet overheat, or a compressor outlet overheat.
What does a FAULT light on #2 mean?
-A disagreement between the selected and actual positions of the pack flow control valves
-A compressor outlet overheat
-A Pack outlet overheat
What does the white “OFF” light mean on #2?
The Pack 1 pushbutton is selected off
What does a fault light on #3 mean?
-Overpressure downstream of the engine bleed valve
-Bleed overheat
-Wing or engine bleed leak (on associated side)
-Bleed valve not closed during engine start
-Bleed valve not closed with APU bleed pushbutton selected
-HP valve failed on the ground
-Single BTS failure or BTS disagree on the ground
-Dual BTS failure in flight or on the ground
-Fan Duct burst detected by the FADEC (Leap 1A engine only)
What does the “OFF” light in #3 mean?
Illuminates when the bleed valve, fan air valve, and HP valve have all closed
What does the fault light on #5 mean?
Indicates an APU leak is detected
What does the “ON” light on #5 mean?
Illuminates when the APU bleed PB is selected ON
With #6 selected to AUTO, when will the crossbleed valve be opened?
It opens if the APU bleed valve is open. It closes when the APU bleed valves are closed, or in the case of a wing, pylon, or APU leak.
What does the fault light on #9 mean?
Illuminates when a duct overheat is detected (88ºC or 190ºF). If this occurs the hot air pressure regulating valve and the trim air valves close automatically. The light will extinguish when the temp drops below 70ºC and the HOT AIR pushbutton is selected off.
Which valve is #4 and what position is it in?
It’s the pack flow control valve, and the valve is open.