3. AIR CONDITIONING
Air conditioning is the process of altering the properties of air
to create more comfortable conditions, typically with the aim
of distributing the conditioned air to an occupied space to
improve thermal comfort and indoor air quality.
Air conditioning can refer to any form of technology that
modifies the condition of air (heating, cooling, de-
humidification, cleaning, ventilation, or air movement).
4. HUMAN COMFORT
The four atmospheric conditions which affect human comforts are
Temperature
Humidity
Air purity
Air Movements
An air conditioner controls the above factors for us to achieve human comfort.
90% of the people are comfortable when the air temperature is between 18-
22°C and the %sat is between 40-65%.
5. AIR HANDLING UNIT
An Air Handling Unit or AHU is a central air conditioner station that handles the air that,
usually, will be supplied into the buildings by the ventilation ductwork.
It is a large metal box containing a blower, heating or cooling elements, filter racks or
chambers, humidity & temperature control loops.
6. CHILLER
Chiller removes heat from a liquid via vapour-compression or absorption refrigeration
cycle.
This cooled liquid flows through pipes in a building and passes through coils in air
handlers, fan-coil units, or other systems, cooling and usually dehumidifying the air in the
building.
Chillers are of two kinds:
1. Air Cooled
2. Water Cooled
7. COOLING TOWER
The Cooling tower cools the warm water by contacting with unsaturated air. The
evaporation of water mainly provides cooling.
Water-cooled chillers are normally more energy efficient than air-cooled chillers.
8. TYPES OF AIR CONDITIONING SYSTEMS
The choice of which air conditioner system to use depends upon a number of factors including
how large the area is to be cooled, the total heat generated inside the enclosed area, etc.
An HVAC designer would consider all the related parameters and suggest the system most
suitable for your space.
Window Air Conditioner
Split Air Conditioner
Packaged Air Conditioner
Central Air Conditioning System
9. WINDOW AIR
CONDITIONER
Window air conditioner is the most commonly used air conditioner for single
rooms. In this air conditioner all the components, namely the compressor,
condenser, expansion valve or coil, evaporator and cooling coil are enclosed in a
single box.
This unit is fitted in a slot made in the wall of the room, or more commonly a
window sill.
10. SPLIT AIR
CONDITIONER
The split air conditioner comprises of two parts: the outdoor unit and the
indoor unit.
The outdoor unit, fitted outside the room, houses components like the
compressor, condenser and expansion valve.
The indoor unit comprises the evaporator or cooling coil and the cooling
fan. For this unit you don’t have to make any slot in the wall of the room.
A split air conditioner can be used to cool one or two rooms.
11. PACKAGED AIR
CONDITIONER
This kind of air conditioner is used to cool more than two rooms or a larger space at your
home or office. There are two possible arrangements with the package unit. In the first
one, all the components, namely the compressor, condenser expansion valve and
evaporator are housed in a single box.
The cooled air is thrown by the high capacity blower, and it flows through the ducts laid
through various rooms. In the second arrangement, the compressor and condenser are
housed in one casing. The compressed gas passes through individual units, comprised of
the expansion valve and cooling coil,
located in various rooms.
12. CENTRAL AIR CONDITIONING
SYSTEM
Central air conditioning is used for cooling big buildings, houses, offices, entire hotels,
gyms, movie theatres, factories etc. If the whole building is to be air conditioned, HVAC
engineers find that putting individual units in each of the rooms is very expensive
making this a better option.
A central air conditioning system is comprised of a huge compressor that has the
capacity to produce hundreds of tons of air conditioning. Cooling big halls, malls, huge
spaces, galleries etc. is usually only feasible with central conditioning units.
14. CASE STUDY
KENZ FURNISHING
LOCATION: THONDAYAD BYPASS,
OPP HILITE MALL
NO. OF FLOORS: 5
FUNCTION: FURNITURE AND INTERIOR DECOR
TYPE OF AIR CONDITIONING USED – SPLIT AC SYSTEM
O
C
A
T
I
O
N
15. CASE STUDY
A series of outdoor units are provided on
the exterior side of the building
10 outdoor units are provided on
this facade
19. CASE STUDY
TYPE OF AIR CONDITIONERS USED: LG L-VOGUE
TECHNICAL SPECIFICATIONS:
Tonnage Range
Cooling(watts)
Compressor
Power Supply(Volt/Phase/Hz.)
Power Input (Watts)
Running Current(Amps)
2.0TR
6350
Rotary - R22
230 / Single / 50
2000
9.2
20. CASE STUDY
PERFORMANCE
Star Rating
Noise Level (Indoor)(dB)
3
40
DIMENSIONS
Indoor (mm)(WxHxD)
Outdoor (mm)(WxHxD)
1090 x 300 x 218
870 x 655 x 322
WEIGHT
Indoor (Kg)
Outdoor (Kg)
13
47
21. HVAC BYLAWS
ASHRAE (AMERICAN SOCIETY FOR HEATING, REFRIGERATION AND AIR
CONDITIONINNG ENGINEERING)
Air-conditioning and ventilating systems circulating air to more than one floor or floor
area shall be provided with dampers designed to close automatically in case of fire and
thereby preventing spread of fuel or smoke
From fire safety point of view, separate air handling units for the various floors shall be
provided so as to avoid the hazards arising from spread of fire and smoke through the
air-conditioning ducts. The requirements of air-conditioning ducts shall be in accordance
with good practice
22. HVAC BYLAWS
DUCT SYSTEM — A continuous passageway for the transmission of air which, in addition
to the ducts, may include duct fittings, dampers, plenums, and grilles and diffusers.
REFRIGERANT — The fluid used for heat transfer in a refrigerating system, which absorbs
heat at a low temperature and low pressure of the fluid Ad rejects heat at a higher
temperature and higher pressure of the fluid, usually involving changes of, state of the
fluid.
23. HVAC BYLAWS
RECIRCULATED AIR — The return air that has been passed through the
conditioning apparatus before being re-supplied to the space.
PLENUM — An air compartment or chamber to which one or more ducts
are connected and which forms part of an air distribution system. The
pressure drop and air velocities in the plenum should be low. Generally,
the velocity in plenum should not exceed 1.5 to 2.5 m/s.
24. HVAC BYLAWS
• CHILLERS:
• Sizing and selecting a chiller is an important aspect in
noise control. The following guidelines may be
considered for noise control:
• For rooftop installation of chillers, these may
be placed on beams connected on the elevated levels of
pillars on correctly chosen vibration isolators.
• Water cooled chillers have less vibration. However, if
air cooled chillers have to be chosen, choose them with fan
of less speeds and compressors must be jacketed without
compromising their ventilation requirement.