3. I’m going to discuses
• Introduction
• Principles of air-conditioning
• Cooling cycle
• Type of air-conditioning
• Application
4. INTRODUCTION
Definition - Air conditioning is the process of
altering the properties of air to more favorable
conditions.
The control of these conditions may be
desirable to maintain the health and comfort of
the occupants, or to meet the requirements of
industrial processes irrespective of the external
climatic conditions
5. PRINCIPLES OF AIR-
CONDITIONING
• The low-pressure liquid refrigerant absorbs heat as it
vaporizes in the evaporator coils. The process described
above is the AIR-CONDITIONING System.
• It is the system on which virtually all modern Air-
Conditioning and refrigeration is based.
6.
7. Air-Conditioning Cycle
• The refrigerant comes into the compressor as a low-pressure
gas, it is compressed and then moves out of the compressor
as a high-pressure gas.
• The gas then flows to the condenser. Here the gas condenses
to a liquid, and gives off its heat to the outside air.
• The liquid then moves to the expansion valve under high
pressure. This valve restricts the flow of the fluid, and lowers
its pressure as it leaves the expansion valve.
• The low-pressure liquid then moves to the evaporator, where
heat from the inside air is absorbed and changes it from a
liquid to a gas.
• As a hot low-pressure gas, the refrigerant moves to the
compressor where the entire cycle is repeated.
8.
9. Types of Air Conditioning System
• Window air-conditioning system
• Split air-conditioning system
• Centralized air-conditioning system
• Package air-conditioning system
10. Window Air-Conditioning System
It is a single unit that is assembled in a casing where all the
components are located
This Air-Conditioning unit has a double shaft fan motor with
fans mounted on both sides of the motor. One at the
evaporator side and the other at the condenser side.
11. Part of Window AC
• Front Panel
• Indoor Side Components
• Outdoor Side Components
12. Front Panel
• The front panel is the one that is seen by the user
from inside the room where it is installed
• The front panel has adjustable horizontal and
vertical(some models) louvers where the direction of
air flow are adjustable to suit the comfort of the
users
• The fresh intake of air called VENT (ventilation) is
provided at the panel in the event that user would
like to have a certain amount of fresh air from the
outside.
16. Split Air-Conditioning System
• 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).
• Further, the present day split units have aesthetic looks and
add to the beauty of the room. The split air conditioner can be
used to cool one or two rooms
17.
18. Centralized Air-Conditioning
System
• The outdoor unit contains the condenser coil, compressor,
electrical components and a fan.
• The evaporator coil, which is usually installed on top of the gas
furnace inside the home.
• A series of pipes, or refrigeration lines, connecting the inside
and outside equipment.
• Refrigerant, the substance in the refrigeration lines that
circulates through the indoor and outdoor unit.
• Ducts that serve as air tunnels to the various spaces inside
your home.
• A thermostat or control system to set your desired
temperature.
19. Central AC’s main Components
• The condenser – is the unit that sits outside your home and contains the compressor,
condensing coil, fan and motor and all the system’s electrical components.
• The evaporator – also known as the A coil - because of it’s A shape, is installed inside your
furnace’s duct system. This coil must be properly matched to the outside unit and should
always be replaced when you purchase a new cooling system in order to maintain
maximum system efficiency and prolong the life of your new air conditioner.
• The line set – The line set is the copper tubing that connects the evaporator to the
condenser. The black insulation or armaflex on this tubing keeps it from sweating as the
cold refrigerant passes through it. The line set can normally be reused as long as it is
properly sized, has no leaks and we are using the same type of refrigerant. We will cover
the two types of refrigerants in just a moment.
• The blower – The blower is provided by your heating system, in other words, your
furnace. This is arguably the most important part of your cooling system. Everything your
new cooling system is capable of doing is dependant upon proper airflow through the A
coil. If your blower is old or dirty it may move too little air and the cooling system will
freeze up. Poor airflow will cause your lower level to get very cold and your upper floors to
get very warm. This is a very common problem and one reason many customers consider
replacing older furnaces when they replace their cooling system – the heat works fine but
the airflow is marginal. However, if your furnace blower is in good shape replacing your
heating system is not necessary.
20.
21. Packaged Air Conditioner
• Packaged air conditioners are similar to window air
conditioners since all the components are housed in one
single unit. Unlike window A/Cs, however, packaged air
conditioners are installed outside your home, usually on the
roof, and can cool the whole building. Some even contain a
heating system, such as a furnace, eliminating the need for a
separate furnace indoors
22. Two types of condensers are
used in packaged systems
• Air-cooled – These condensers are cooled by the surrounding
air. These are more common for residential use.
• Water-cooled – These condensers require a cooling tower, so
they’re used primarily for large commercial applications where
water is plentiful.
23. Packaged Air Conditioners
with Air Cooled Condensers
• In this packaged air conditioners the condenser of the refrigeration
system is cooled by the atmospheric air. There is an outdoor unit
that comprises of the important components like the compressor,
condenser and in some cases the expansion valve (refer the figure
below). The outdoor unit can be kept on the terrace or any other
open place where the free flow of the atmospheric air is available.
The fan located inside this unit sucks the outside air and blows it
over the condenser coil cooling it in the process. The condenser coil
is made up of several turns of the copper tubing and it is finned
externally. The packaged ACs with the air cooled condensers are
used more commonly than the ones with water cooled condensers
since air is freely available it is difficult maintain continuous flow of
the water.
• The cooling unit comprising of the expansion valve, evaporator, the
air handling blower and the filter are located on the floor or hanged
to the ceiling. The ducts coming from the cooling unit are connected
to the various rooms that are to be cooled.
24.
25. Application of AC
• The main function of an air conditioning system is mainly
to produce cooling inside the room
• Removal of heat
• Decrease temperature for comfort
• Use in offices, home & class rooms
• The central air conditioning plants or the systems are
used when large buildings, hotels, theaters, airports,
shopping malls etc. are to be air conditioned completely.
