This document provides an overview of integrated building management systems and HVAC systems. It discusses the objectives of learning about IBMS and provides a syllabus covering various building systems. It then focuses on HVAC systems, explaining concepts like psychrometry, the vapor compression cycle, components of HVAC systems, and factors affecting human comfort. Key terms are defined, such as one ton of refrigeration, COP, IPLV, dew point temperature, and relative humidity. Diagrams illustrate the vapor compression cycle and psychrometric processes.

1. Integrated Building Management Systems (IBMS)
Objectives of learning this subject

3. Integrated Building Management Systems (IBMS)
Syllabus
• Basic Types of service
• Importance of IBMS
• HVAC Systems
• Electrical systems
• Lighting
• Fire Fighting systems
• Vertical transportation
• Water proofing
• Plumbing
• Building security

4. HVAC Systems
Major Topics
• What is HVAC
• Need for HVAC
• HVAC fundamentals
Working of VCC and VAM
Human comfort, Psychrometry,
Psychrometry terms,
• HVAC systems
• Alternatives to active HVAC systems
• Indoor air quality
• Introduction to Green buildings

5. Understanding
HVAC

6. Refrigeration fundamentals
It is cooling by removal of heat
It is transfer of heat from where it
is not wanted to a place where it is
not objectionable.

7. Air Conditioning
The process of treating air so as to
control simultaneously its temperature,
humidity, cleanliness and distribution
of the conditioned space.
ASHRAE

8. Human Comfort
Comfort
Condition of mind which expresses
satisfaction with surrounding
environment.

10. What we say about
discomfort
What the air conditioner
does
It is too warm The air is cooled
It is too cold The air is warmed
It is too stuffy The conditioned air is
circulated gently
It is dusty or smoky The air is filtered
There is an unpleasant
odour
The bad air is exhausted
and fresh air is taken in
The air is stale The air is mixed with fresh
outdoor air

11. Human Comfort
Temperature
Humidity
Filtration
Distribution

12. Filtration

14. Understanding:
• TR
• Heat

15. BTU
British Thermal Unit
Amount of heat required to raise One
Pound of Water by One degree
Fahrenheit.

16. Cooling obtained by uniform melting
of 1 US tonne of ice at 0 0C within 24
hours.
Significance: It indicates system’s
cooling capacity.
Ton of Refrigeration (TR):

18. F = 0 0C

20. One TR is approximately equal
• 12000 Btu/hr
• 3.517 kW
• 3024 kcal/hr

22. Heat

26. Types of Heat

27. Concepts
1. Sensible heat and latent heat

28. 0 0C 100 0C
Sensible Heat

29. Sensible Heat

30. 100 0C 100 0C
Latent Heat

31. Latent Heat

33. - 5 0C
5 0C
- 5 0C
5 0C

34. • Understanding working of Vapour
Compression Cycle
• COP, EER, SEER, IPLV
• Air Conditioner Vs Heat Pump
• Understanding Comfort Air Conditioning
fundamentals
Psychrometry
DBT, WBT, DPT, RH
Summer and Winter Air
Conditioning

35. Understanding working of Vapour
Compression Cycle (VCC)
Basic Components
• Evaporator
• Compressor
• Condenser
• Expansion valve (Metering device)

36. Vapour
Compression
Cycle (VCC)

37. Indoor Unit
Evaporator
Expansion valve
(metering device)

38. Outdoor Unit
Condenser
Compressor

39. Function of each component of VCC
1. Evaporator: It is heat exchanger where the refrigerant
picks up the heat and cools the surrounding.
2. Compressor: The function of compressor is to increase
the temperature and pressure of refrigerant so that the
refrigerant is able to reject the heat in the condenser.
3. Condenser: The condenser is a heat exchanger where the
refrigerant rejects the heat absorbed to the surroundings.
4. Metering device (Expansion valve): The function of
metering device is to reduce the temperature and pressure
of the refrigerant entering the evaporator so that the
refrigerant is able to absorb the heat in the evaporator.

40. Vapour Compression Cycle (VCC)
Qcondenser = Qevaporator + Qcompressor

41. Schematic of vapour compression cycle
1
2
2a3a
3
4
Qcondenser = Qevaporator + Qcompressor

42. Thermostatic
expansion valve
Electronic
expansion valve
Plate type
Shell & tubes
W/c Shell &
tubes
A/c Coil
Reciprocating
Screw
Centrifugal
Vapour Compression Cycle

43. Centrifugal
Screw
Reciprocating
Scroll
Compressors

44. Shell & Tube DX
Evaporator
Fin & Tube
type H/E
Plate Heat
Exchanger
Heat Exchangers
(Condensers and Evaporators)

45. Thermostatic Expansion Valve Electronic Expansion Valve
Expansion Devices

46. Working of VCC
(Refer Animation Attached)

47. Working of Domestic
Refrigerator
(Refer Animation Attached)

48. • COP: Coefficient of Performance
Ratio of Refrigerating effect (or cooling
effect) to work input to the compressor.
In some situations, it is also expressed as
EER (Energy Efficiency Ratio). SEER
stands for Seasonal Energy Efficiency
Ratio
COP

49. • Integrated Part Load Value
Performance of system at various part
load conditions (e.g. 100 %, 75 %, 50 %,
25 %)
IPLV

50. Vapour Absorption Refrigeration
Only Compressor of Vapour Compression
cycle (VCC) gets replaced by:
1. Absorber
2. Pump and
3. Generator
Remaining components similar to that
present in VCC

51. Heat pump
Maintains temperature of system higher
than the surrounding.
Used for heating applications (space
heating, hot water generation)
Working cycle same as air conditioner
except the sequence of operation is
exactly reverse to that of air conditioner

53. Draw a schematic of vapour
compression cycle and explain
the functions of each component
Explain the significance of
• TR
• COP
• IPLV

54. Explain the difference between
Air conditioner and a heat
pump?
Can a air conditioner work as a
heat pump?

55. 1. One ton of refrigeration (TR) is
approximately equal to ___.
a. 3024 kcal/h
b. 3.517 kW
c. 12000 Btu/hr
d. All of the above
d) All of the above

56. Latent heat is more important than
sensible heat in refrigeration cycle
a) True b) False
a) True

57. Does the heat loss from the
condenser is equal to the heat gain
to the evaporator?
a) It is more
b) It is less
c) They are equal
d) They are equal only after
running for a certain time
(Answer : a )

58. Which of these could be the
possible value of Heat Rejection
Factor (HRF)
a) 0.8
b) 1.0
c) 1.2
d) 0.9
(Answer : c )

59. Which of the following has better
energy efficient performance?
a. 1.2 kW / TR
b.1 kW / TR
c. 0.7 kW / TR
d.1.5 kW/TR
(Answer : c )

60. Room heaters are more efficient
than heat pumps for heating
application
a. True
b.False
(Answer : b )

61. Psychrometry

62. Willis Haviland Carrier
was an engineer and inventor, and is known as the
man who invented modern air conditioning.

63. Psychrometry

64. It is a branch of Engineering Science
which deals with the study of Moist Air
(i.e. dry air mixed with water vapour).
Psychrometry
Psychro metry
Properties of Measurements
moist air
Psychrometry

65. % By Volume

66. • DBT
• WBT
• DPT
• RH
Psychrometric terms

67. • Dry Bulb Temperature (DBT):
Dry-bulb temperatures are read from an
ordinary thermometer that has a dry bulb.
( not exposed to moisture as well as radiation)
Psychrometric terms

68. • Wet Bulb Temperature (WBT):
The temperature of air recorded by a
thermometer, when its bulb is surrounded by
a wet cloth and is exposed to moving air at a
velocity of 2.5 – 5 m/s.
Wet bulb depression: Difference between
DBT and WBT

69. Device which measures DBT and WBT
simultaneously is called Sling Psychrometer.

70. • Significance of WBT:
• Higher the WBT, humid is the air.
• Lower the WBT, dry is the air.
• At 100 % Relative humidity, DBT= WBT

71. • Dew Point Temperature (DPT):
The temperature at which condensation of
moisture begins when the air is cooled.

72. • Significance of DPT
• Condensation occurs at Dew Point.
• Therefore if we want to dehumidify (remove
moisture) air then it should be brought in
contact with a surface whose temperature is
below Dew Point Temperature of air.
• Dew Point is important for Dehumidification
Applications.

73. • Humidity ratio:
It is mass of water vapour present per kg of
dry air and is generally expressed as gram
per kg of dry air.

74. • Relative Humidity:
(How much moisture in the air)
(How much it could hold at saturation)
at same temperature
Relative humidity is expressed in
terms of percent.

75. Humidity ratio
(It signifies quality of air)
Vs
Relative humidity
(Signifies Human Comfort)

76. Fog
Fog occurs when air is saturated

77. Condensation
Condensation occurs at Dew Point

79. SHF
= Sensible Heat
_______________________________________
(Sensible + Latent heat)

80. Latent Heat Concept
• Latent heat is considerably larger than
sensible heat.
• In VCC cycle, we use the concept of latent
heat in evaporator. This reduces the
quantity of refrigerant required and makes
the system compact.
• However, for air conditioning applications,
the latent load due to moisture is critical.

81. Latent Heat Concept
• In Air conditioning, moist air has two
components i.e. dry air and moisture. Dry air
remains in gaseous phase in the air conditioning
operating range. However only moisture changes
its phase (dehumidification / humidification)
• Since latent heat (phase change) is considerably
larger, in air conditioning application, latent load
due to moisture becomes significant especially
near highly humid areas such as coastal climatic
conditions. This increases the cooling
requirement (TR capacity).

82. Review of Psychrometry

84. Explain significance of WBT, DPT
Identify the Psychrometric process
generally used for summer and winter
conditions
Define Human comfort. List the
factors affecting human comfort.
What are the typical values of
Temperature, RH, Velocity for comfort
air conditioning.

85. For same DBT, WBT of Pune will
be higher than Chennai
a. True
b.False
(Answer : b )

86. The process used in comfort air
conditioning for summer season is
a. Heating and humidification
b.Cooling and humidification
c. Cooling and dehumidification
d.Heating and dehumidification
(Answer : c )

87. Which temperatures plays a
significant role in dehumidification
applications
a. DPT
b.WBT
c. DBT
d.All of the above
(Answer : a )

88. Which combination will make a person
feel uncomfortable?
a) decrease temperature, increase humidity,
decrease air motion
b) increase temperature, increase humidity,
increase air motion
c) increase temperature, decrease humidity,
decrease air motion
d) increase temperature, increase humidity,
decrease air motion
Answer: d

89. References:
1. Carrier Corporation Training Material
2. Trane Air Conditioning Handbook
3. ASHRAE Fundamentals Handbook
4. Ramesh Paranjpey, Basics of Air Conditioning
5. P.N. Ananthanarayanan, Basic Refrigeration and Air Conditioning
6. R.S. Khurmi and J.K. Gupta, Refrigeration and Air Conditioning