Civil Engineering Reference
In-Depth Information
Chapter 8
HVAC Systems
8.1
Early Years
Wind tower structures were used to provide natural air conditioning and humidifi -
cation in hot and dry climates in central parts of ancient Iran. As wind entered to
the structure from the top of the tower and through the fl aps it was directed down
inside of the building and therefore created a sense of air movement for the people
inside the building. A cistern in the bottom of the tower used to create some sort of
humidity control inside the tower as the air passed over it.
Samuel Sugarman in his topic “HVAC Fundamentals” (Sugarman
2007
) has a
comprehensive look at HVAC systems history and operations. Regarding the history
of HVAC systems, he depicted a timeline starting year 1000 and has divided it into
four major recognizable eras. In fi rst 500 years of this timeline, some of the main
HVAC related inventions were invention of fans that were operating either by man
power or water power in Egypt and Italy. In the following 200 years some of the
major HVAC-related inventions were included utilization of ventilating machines
for ventilating the mines which was invented in France, invention of thermometer
by Galileo and development of a thermometer independent from the air pressure by
Ferdinand II. Between years 1700 and 1900 Fahrenheit invented mercury thermom-
eter, Benjamin Franklin invented fi rst steam heating system followed by James
Watt's steam engine; Carnot founded thermodynamics and James Joule discovered
that work produces heat, and heat started to be considered as energy. In this era law
of conservation of energy was discovered, along with fi rst and second laws of
thermodynamics. Finally after year 1900, HVAC systems improved dramatically
and systems such as furnace with centrifugal fans, and high pressure steam heating
systems were widely utilized. First centrifugal refrigeration machine was made for
air conditioning of the large spaces. Pumps and radiators started to be utilized and
fi rst refrigeration system with a compressor was invented which led to residential air
