Air Conditioning Flashcards
In high ambient temperatures on the ground (greater than +35C) after APU start, how can the cabin be cooled down most efficiently?
Select full cold Manual Mode, close all doors, minimize electrical loads.
What is the function of the RAM AIR switch?
Closes both air conditioning pack valves (Pack Inlet Valves - PIVs), allowing outside air to the cabin (when Ram Air pressure > Cabin Pressure)(check valve).
What is the function of the AUTO TEMP SELECT switch?
Allows auto temp selection to be displayed on the overhead temperature display panel.
What is the function of the TEMP DISPLAY ZONE switch selection?
Allows the ACTUAL temperatures of the cockpit/forward/aft zones to be displayed in the overhead display window.
What is the function of the TEMP DISPLAY DUCT switch selection?
Allows the actual temperature of each duct forward of the trim air valves (after mixing cool and hot air) to be displayed in the overhead display window.
What is the function of the AUTO / MANUAL SELECT switches?
Allows the rheostat to set desired temperature in the AUTO or MANUAL position.
What is the temperature range of the AC system rheostat controls in the AUTO position?
60-90F
What is the temperature range of the AC system rheostat controls in the MANUAL position?
35-230F
How does the engine START switch and START MASTER switch affect operation of the air conditioning packs?
START MASTER - turns off the Right Pack
Engine START switch - turns off the Left Pack
How is moisture from the pack air output used to improve system efficiency?
Moisture removed from the air by each pack is sprayed into the duct above the heat exchangers, making them more efficient.
If a cabin overhead vent (gasper) is opened, what will the temperature of the air coming out of it be?
Slightly warmer than freezing (35F)
