On this day in 1939, the 40th National Automobile Show opened in
Chicago, Illinois, with a cutting-edge development in automotive
comfort on display: air-conditioning. A Packard prototype featured
the expensive device, allowing the vehicle's occupants to travel in
the comfort of a controlled environment even on the most hot and
humid summer day.
After the driver chose a desired temperature, the Packard
air-conditioning system would cool or heat the air in the car to
the designated level, and then dehumidify, filter, and circulate
the cooled air to create a comfortable environment. The main
air-conditioning unit was located behind the rear seat of the
Packard, where a special air duct accommodated two compartments,
one for the refrigerating coils and one for the heating
coils.
The capacity of the air-conditioning unit was equivalent to 1.5
tons of ice in 24 hours when the car was driven at highway driving
speeds. The innovation received widespread acclaim at the auto
show, but the expensive accessory would not be within the reach of
the average American for several decades. However, when automobile
air-conditioning finally became affordable, it rapidly became a
luxury that U.S. car owners could not live without.