Environmental Control System Flashcards
What function does the Pneumatic Valve Assembly (PVA) fitted to each engine provide for the Environmental Control System (ECS)?
Controls the continuous P3 bleed-air requirement
Where is the Pressure Regulating and Shutoff Valve (PRSOV) located?
In the left engine compartment
What is the function of the Pressure Regulating and Shutoff Valve (PRSOV)?
To act as an ON/OFF supply valve, regulate engine bleed-air pressure to the Heating and Ventilation System (HVS) and remove pressure variations and surges associated with engine performance
What happens if the HVS fan over heats?
The entire heating system latches off, requiring power to be recycled when cool, to reinitiate the system
Where is the Cockpit and Cabin Heating and Ventilation System (CCHVS) fan located?
On the left side of the aircraft in the rear bay
How is the Heating and Ventilation System (HVS) fan distribution ducting protected against overpressurisation?
The system has two, permanently open, under seat foot vents
Where are the controls for the Heating and Ventilation System (HVS) located?
To the left of the Engine Control Panel (ECP) on the overhead console
What is the Environmental Control System (ECS) response if an [HVS DUCT HOT] caution illuminates on the Warnings, Cautions and Advisories (WCA) display?
The system is latched off
What is the heating operational response from the Environmental Control System (ECS) after an [HVS DUCT HOT] Warnings, Cautions and Advisories (WCA) indication illuminates, system temperature is not cooling below 90 °C and a reset is attempted?
The system will not restart until the temperature reaches a normal limit
When must the Forward Avionic Cooling System (FACS) be operated to maintain a thermal environment?
Whenever power supplies are selected “ON”
How is water ingress prevented on the Forward Avionic Cooling System (FACS)?
Inlet duct design slows the airstream allowing for water particulates to drop and be expelled via drains on the lower fuselage
Where are the switches for the Forward Avionics Cooling System (FACS) located?
On the right side of the overhead console
Assuming both AC and DC power is available if both FACS fans are put to auto what state are the fans in?
Primary fan is running and secondary is off.
Why are there two rear bay cooling fans?
Redundancy
How may load sharing between the two Rear Bay Cooling System (RBCS) fans be achieved?
By manually alternating the fan selection on alternate days to balance operating hours
How is a Rear Bay Cooling System (RBCS) [RBCS FAN] caution cleared after a single fan failure without switching the system to OFF?
By selecting the alternate RBCS fan (non-failed) to ON
