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1. GANDHINAGAR INSTITUTE OF
TECHONOLOGY(012)
SUBJECT : Refrigeration & Air Conditioning
(2161908)
Active Learning Assignment on the topic of
“Air Conditioning System”
BE Mechanical
Prepared By: Yash D. Pandya
Guided By :

2. OVERVIEW
 Classification
 Selection of air conditioning system
 Groups of the system
 System Equipments
 Reference

3. Classification
 Air conditioning is the process of maintaining temprature and
moisture within an occpied space.
 The air conditioning system can be broadly classified into two
types:
 This system is also classified Based on season of year…
i. Winter air conditioning system
ii. Summer air conditioning system
iii. Year round air conditioning system
i. Unitary system
ii. Central system

4. Unitary System
 These systems are manufactured and assembled as one unit in a factory
and brought to the site and installed.
 This makes the system cheaper due to mass production.
 This system have better workmanship due to quality control that is
possible only in factory.These are also easy to install.
 Some of the unitary systems are:
i. Window A/C
ii. Split A/C
iii. Package A/C

5. Central System
 These systems are assembled at the site after procuring different
equipments from various manufactures.
 The systems are more economical in first cost as well as in
running cost at higher capacities.
They are capable of giving stringent and uncommon conditions in
space as required in some technical applications.
 Generally capacity of central air conditioning system is more then
30 TR.

6. Selection of air conditioning system
An AC system should satisfy the need of user at the most economical
cost.
 The selection of system depends upon many factors:
 Customer’s objectives
 Economics
 Occupancy
 Thermal load
 Internal environment

7. Groups of air conditioning system
 The systems are broadly divided into four groups:
1. Direct expansion system
2. All Water system
3. All Air system
4. Air-Water system

8. All Water System
 Schematic diagram for all water system is shown in below figure.
Advantages:
 The plant size is small due to the absence of large supply air fans.
 The thermal distribution system requires very less space compared to
all air systems.
Disadvantages:
 It requires high maintainence compare to all air syatem.
 The filters are small, low in efficiency and require frequent replacement.
 Control of humidity, particularly during summer is difficult using
chilied water control valves.

9. All Air System
 Schematic diagram for all air system is shown in below figure.
Advantages:
 Avoid noise in the conditioned space.
 It is possible to provide simultaneous cooling and heating.
 Seasonal change over is very simple and easy to automate.
Disadvantages:
 It requires more space reduces available floor space.
 Due to space constraints it may be difficult to provide air
conditioning in high rise buildings with the plant on the ground floor
or basement.

10. Air-Water System
 Schematic diagram for all air-water system is shown in below figure.
Advantages:
 The amount of primary air supplied is less than that of an all air systems
therefore, space requirement is reduced.
 Rooms can be individually controlled at relatively low cost, which control
either the secondary water flow rate or the secondary air or both.
Disadvantages:
 Handling and controlling of both water and air is difficult.
 Initial cost is very high compare to other system.
 Need more mintainence.

11. Air Conditioning Equipments
 An air conditioning system has processing equipments fitted in Air
Handling Unit (AHU).
 These are :
i. Air cleaner: For filtration of air.
ii. Cooling coil: For cooling and dehumidification of air in summer.
iii. Heating coil: For heating in winter or as reheaters in summer.
iv. Fan: For circulation air through entire AC system.
v. Humidifiers: For adding moisture to the air.

12. Thank You