"Peter Duniho" wrote

At what point is it that you believe moisture is actually *removed*
from the cabin air in an airliner?

Qouting from my B-707 and B-727 Flight Manuals:

WATER SEPARATOR
A water separator is installed in the Air Cycle Machine turbine
output duct to remove water by centrifugal action from the cold
air.
ANTI-ICING CONTROL VALVE
An anti-icing control valve is installed to automatically route
warm air from the Primary Heat Exchanger into the water separator
to prevent icing when airflow temperature drops below 40 degrees.


When the water separator valve does ice-up, it starts snowing
from the air conditioning vents in the cabin.

Bob Moore
17 years in the Boeing 707
PanAm (retired)