1. TYPES OF AIR CONDITIONING SYSTEMS

2. BASED ON
ARRANGEMENT
CENTRAL ZONED UNITARY
UNITARY-
CENTRAL

3. PURPOSE
INDUSTRIAL COMFORT/DOMESTIC

4. CENTRAL SYSTEM
Central AC Systems serve several rooms, the entire system is monitored centrally
using a thermostat
The condenser, compressor, cooling a humidifying coils are located outside the area
that has to be air conditioned.
Air is circulated through ducts. Central air conditioning system follow a combination
of open and closed cycles of operation. Some of the air is exhausted to the
atmosphere while some portion is re-used

7. PRIMARY AIR FILTER
SECONDARY AIR FILTER (ELECTROSTATIC/FABRIC)
PREHEATER COIL
TEMPERATURE
AND HUMIDITY
CONTROL
RECIRCULATED
AIR
CONDENSOR COIL
DEHUMIDIFIER
FAN

8. APPLICATIONS
 Big factory spaces
 Movie Theatres
 Restaurants
 Auditoriums
 Homes

9. CENTRALSYSTEM
ADVANTAGES
The temperature of a very large space
can be regulated.
Noise is less as operating equipment is
placed outside
Low investment cost when compared to
individual units
The exhaust air can be re-used
Though the cost to set-up the unit, the
running cost per unit of refrigeration is
less
DISADVANTAGES
Very large set-up, occupies plenty of
space.
Cost of components like compressors,
cooling tubes, ducts are high.

10. UNIT SYSTEM
In this system, equipment and control mechanisms are packed into a single unit
These are generally used for room air conditioning, as attic fans and remote units
They are generally installed in or near the vicinity of the space that has to be cooled.

12. ATTIC FAN

15. UNIT SYSTEM
ADVANTAGES:
 Cost of installation is low
 Individual room temperature control is possible
 Failure of a unit affects only the area that was served by that unit
 It is sufficient to install units in only the rooms where cooling is essential.

16. HUMIDITY CONTROL

17. WHATIS HUMIDITY?
Humidity is the amount of water vapour in the atmosphere.
Humidity is measured using a
Psychrometer or Hygrometer

18. WHYCONTROLHUMIDITY?
 Comfort-This is why air conditioners were introduced in the first place.
 Storage and Preservation
1. To prevent corrosion
2. Mildew and Mould prevention
3. To prevent condensation

20. HOWITHAPPENS
The process of humidity control can be classified as
 Mechanical dehumidification
Desiccant dehumidification

21. MECHANICALDE-HUMIDIFICATION

23. MECHANICAL DEHUMIDIFIER

24. DISADVANTAGESOFMECHANICAL
DEHUMIDIFIERS
Very noisy operation
Economical only when used in regions where humidity and temperature are high
(above 40% RH)
The compressor unit consumes a large amount of electric power

25. DESICCANT DEHUMIDIFIER

27. DESICCANT DEHUMIDIFIER

28. MATERIALS USEDINDESICCANT
DEHUMIDIFIERS
Zeolites:
-Silica Gel
-Clinitilophite
-Chabazite

29. APPLICATIONS
PHARMACEUTICAL & BIOMEDICAL INDUSTRY
 Any substance has affinity for moisture.
 Moisture absorption can affect critical
parameters such as chemical concentration,
thermal expansion
 Desiccant dehumidification is generally used.

30. APPLICATIONS
INDUSTRIAL PLANTS, MILITARY AND ELECTRONICS INDUSTRY
One of the primary functions of de-
humidification is to prevent corrosion
 Moisture acts as a catalyst
Moisture on PCBs and electronic
components can severely impact their
operation.

31. APPLICATIONS
FOOD AND TEXTILE INDUSTRIES
 Moisture and damp conditions are ideal
conditions for the growth of mildew and
mold
 Desiccant dehumidifiers are generally
used as the temperature and humidity
in food storage units are generally low.

32. INDUSTRIAL DEHUMIDIFIER