Introduction to HVAC

1. By Tushar Mistry
B.E. Mechanical

2. H – Heating
V – Ventilating
A – Air
C - Conditioning

3. What are we Going to Learn?
⚫Basicsof refrigeration & HVAC
⚫Working cycles of HVAC
⚫Componentsof HVAC
⚫Functionsof HVAC components
⚫Study Of Compressor & Condenser
⚫Studyof Evaporator & Refrigerants
⚫Refrigerant handling and replacement
⚫Inspection & Breakdown Maintenance
⚫Malls, Hotel, Multiplex, Inspection & Breakdown
Maintenance

4. What is the purpose of HVAC ?
Itconditions theair, transports it, and introduces it to
theconditioned space. Itprovides heating and cooling
from its central plant . It also controls and maintains
the temperature, humidity, air movement, air
cleanliness, sound level, and pressure differential in a
spacewithin predetermined limits for thecomfortand
health of theoccupantsof theconditioned spaceor for
the purposeof productprocessing.

5. What is TR?
⚫1 TR is amount of heat required to melt
one metric ton of ice in 24 hours.
⚫1 TR (Ton of Refrigeration) = 12000 BTU / hr
⚫1 TR (Ton of Refrigeration) = 3024 Kcal / hr
⚫1 TR (Ton of Refrigeration) = 3.51 KW

6. H - Heating
⚫Heat is a form of energy
⚫Molecules in motion
⚫Flows from a substance with more heat to one with less
heat
⚫Unit = Joule (J)
⚫W = J/S = N.M/S

7. Sensible Heat & latent Heat
⚫Sensible Heat
If heatadded orremoved from substance , itchanges it
temperature then itscalled as sensible heat.
⚫Latent Heat
If heat is added orremoved itchanges the stateof
substance then itscalled as latent heat.

9. Heat Transfer Modes
⚫Conductio
n
⚫Convection
⚫Radiation

10. ⚫Specific Heat
Amountof heat required tochangea unit massof
substance byonedegree temperature.
⚫SaturationTemperature
Temperature forcorresponding saturation pressureat
which the liquid boils into itsvapourphase.
⚫Enthalpy
Total heatcontentof the system

11. V - Ventilation

12. A – Air
C - Conditioning
An airconditioning, or HVAC, system is composed of
componentsand equipmentarranged in sequence to
condition the air, to transport it to the conditioned
space, and tocontrol the indoorenvironmental
parameters of a specific spacewithin required limits.

13. Basic Refrigeration Cycle

14. Classification of Air Conditioning
System
⚫According toApplication
1) ComfortAir Conditioning Systems
2) Process Air Conditioning Systems
⚫According to Construction & Operating
Characteristics

15. HVAC
systems
Floor MountedPackage
AirCondition
Package Air
Conditioning
Ceiling Mounted Package
AirConditioning
Ductable
AC
Direct ExpansionSystem
Central Air
Conditioning
IndirectExpansion
System
Non Ductable
AC
SplitAir
Condition
Cascade SplitAC
(Ceiling Mounted)
Floor MountedSplit
AC
WindowAir
Condition
Wall Mounted SplitAC
15

16. Windows Air Conditioning System
⚫ Window air conditioners are one of the most commonly used
and cheapest type of air conditioners.
⚫ Toinstall one of these units, you need the space to make a slot in
the wall, and there should also be some open space behind the wall.
⚫ Window air-conditioner units are reliable and simple-to-install
solution to keep a room cool while avoiding the costly construction of
a central air system.
⚫ Better yet, when the summer heat dies down, these units can be
easily removed for storage, and you can use the window sill for other
purpose

18. Split Air-Conditioning System
Thesplitairconditionercomprises of two parts: the
outdoorunitand the indoorunit
⚫ The outdoor unit, fitted outside theroom, houses
components like thecompressor, condenser and
expansionvalve.
⚫ The indoor unit comprises theevaporatoror cooling coil
and thecooling fan. Forthisunit youdon’t haveto make
anyslot in thewall of theroom.
⚫ Further, the present day split units have aesthetic looks and
add to the beauty of the room. The split airconditioner can
beused to cool one or tworooms

20. Central AC System
⚫ Thecentral airconditioning plantsorthesystemsare
used when large buildings, hotels, theaters, airports,
shopping mallsetc. are to be airconditioned completely
.
⚫ Thewindowand splitairconditionersareused for
singleroomsorsmall officespaces.
⚫ If the whole building is to be cooled it is not
economically viable to put window or split air
conditioner ineachand everyroom.
⚫ Further, these small units cannot satisfactorily cool the
large halls, auditoriums, receptions areasetc.

22. ⚫Air System (AHU)
⚫Water System
⚫Central Plant
⚫Control System

24. Packaged AC System
⚫ Thewindow and splitairconditionersareusually used forthe
smallairconditioning capacitiesupto5 tons.
⚫ Thecentralairconditioning systemsareused for where the
cooling loadsextend beyond 20tons.
⚫ The packaged airconditionersareused forthe cooling
capacities in between these twoextremes.
⚫ Thepackaged airconditionersareavailablein the fixed rated
capacitiesof 3,5, 7, 10 and 15tons.
⚫ These unitsareused commonly in places like restaurants,
telephoneexchanges, homes,small halls,etc.

26. POTENTIALS AND CHALLENGES
⚫Providing a Healthyand Comfortable Indoor
Environment
⚫The Cleanest, Quietest, and Most Preciseand Humid
Processing Environment
⚫Energy Useand Energy Efficiency
⚫Environmental Problems—CFCsand Global Warming

27. Goals of HVAC System
⚫Effectively control indoor environmental parameters,
usually to keep temperatureand humiditywithin required
limits.
⚫Providean adequateamount of outdoorventilation airand
an acceptable indoorairquality.
⚫Useenergy-efficientequipmentand HVAC&R systems.
⚫Minimizeozone depletion and theglobal warming effect.
⚫Select cost-effectivecomponents and systems.
⚫Ensure proper maintenance, easyafter-houraccess, and
necessary fire protection and smoke control systems.

30. THANK YOU