BOMBARDIER BD-100-1A10, Operating Manual

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AIR CONDITIONING/PRESSURIZATION
Volume 2 Flight Crew Operating Manual Sep 13/2004
02-03-04
CSP 100-6
REV 1
AIR CONDITIONING SYSTEM (Cont)
Temperature selectors — Used to select desired temperature for the cockpit and cabin.
MAN TEMP — Used when automatic temperature control using cabin or cockpit ventilation sensors is not
working.
AIR SOURCE selector —
- OFF - both flow control valves will be closed, preventing bleed air for pressurization and air condi-
tioning from entering the cabin
- NORM - The normal switch position. This setting allows bleed air from the left and right sides of
the manifold to flow through the PACK and the TRIM AIR valves, providing conditioned air to the
cabin
- PACK ONLY - Opens the left flow control valve and closes the right flow control valve and pre-
cooler crossover valve (PCV), resulting in all bleed air flowing through the PACK and none
through the trim air valves. This selection is used when a TRIM AIR failure exists. A PACK ONLY
(S) CAS will be displayed.
- TRIM AIR ONLY - Opens the right flow control valve and closes the left flow control valve and
(PCV), resulting in all bleed air flowing through the trim air valves and none through the PACK.
This selection is used when a PACK failure exists. A TRIM AIR ONLY (S) CAS will be displayed.
RAM AIR INLET
Ram air enters the aircraft at the ram air inlet at the base of the vertical fin. Ram air is used as the cooling medium for the
air-to-air heat exchangers. Ram air passes through the secondary, primary, and precooler heat exchangers where heat is ex-
tracted from the air circulated through the air conditioning system. After passing through the heat exchangers, the air is
discharged overboard through the exhaust vents.
On the ground, airflow through the ram air inlet is inadequate for cooling the heat exchangers. A fan located in the ram air
duct, mechanically driven by the air cycle machine, increases airflow through the duct to cool the heat exchangers.
RAM AIR VALVE
If the air conditioning system fails, ram air can be used to ventilate the cockpit and cabin at low altitude. After descending
below 10 000 ft, selecting the guarded RAM AIR switch to ON opens the ram air valve to provide air flow into the aircraft.
RAM AIR — Used to provide ambient air to ventilate the cockpit and cabin, in the event of PACK and
TRIM AIR failure.
COCKPIT
COLD HOT
CABIN
COLD HOT
MAN TEMP
ON
AIR SOURCE
NORM
PACK ONLY
TRIM AIR
ONLY
OFF
CF
O
0203002_0
05
RAM AIR INLET
EXHAUST
RAM AIR
ON