ABSTRACT
The need for an authentic and reliable
report relating to the repairs and rehabilitation of a faulty air-conditioner
is inevitable.
Many homes and offices uses the
air-conditioner to cool he temperature in their respective homes. So the maintenance of the air-conditioner
should be a top priority of every individual in order to avoid huge expenditure
in the repairs of the system. It’s for
this reason that this report is written for the benefit of those whom are
privileged to own an air-conditioner in their respective homes.
This report is based on ordinary and
advanced level research, in order to aid easy reading and understanding for an
average person. This report begins with
an introduction into the relevance of an air – conditioner, the history,
description of the important components of the air – conditioner, the general
maintenance and regular maintenance an serving, one is expected to carryout for
effective performance of the air-conditioner and the faults discovered together
with the repairs carried out.
Subsequently, advanced information
pertaining to the repairs and calculations involving a faulty air conditioner
have been giving certain sections of this report, which will be beneficial to
those interested in the repairs of the faulty air conditioner.
TABLE
OF CONTENTS
Title
Page
Letter of Transmittal
Approval Page
Dedication
Acknowledgement
Abstract
Table of Contents
CHAPTER ONE
1.1
Introduction
1.2
Literature Review
1.3
Definition Of An Air Conditioner
1.4
Why We Use Air Conditioner
1.5
Significance Of Study
1.6
Limitation Of Study
1.7
Basic Components Of Air Conditioner
1.8
Functions Of The Components
1.9
Air Conditioning System And Properties Of Air
CHAPTER TWO
2.1
Statement Of Problem/Faults
2.2
How To Detect The Faults
2.3
Brief Explanation Of Major Tools And Equipment’s Used
2.4
Detecting Of Faults
2.5
Correction Of Faults
2.6
Connection Of The Electrical Components
2.7
Detection Of Shortage Of Gas In The System
2.8
Replacement Of Front Grille And Filter
CHAPTER THREE
3.1
Maintenance
Of Breakdown Air Conditioner
3.2
Causes Of Air Conditioner Breakdown
3.3
What Is Breakdown Maintenance
3.4
Categories Of Maintenance
3.5
Groups Of Air Conditioner Maintenance
3.6
General Maintenance And Repairs Schedules
3.7
Safety Precautions
CHAPTER FOUR
4.1
Principle Of An Air Conditioner
4.2
Mathematical Representations And Thermal Efficiency
4.3
Mathematical Analysis And Calculations
CHAPTER FIVE
5.1 Cost
Analysis
CHAPTER SIX
6.1
Performance
6.2
Conclusion
6.3
References
CHAPTER
ONE
1.1 INTRODUCTION
Over the
years, all the tropical countries have been faced with the problem of air
around them. The relative humidity of
air in most of the tropics is very low; Hence the comfort is not there with the
populace especially in the places of work.
This consequently reduces the work rate of workers thereby affecting the
GROSS NATIONAL PRODUCT of a country.
To this effect, the engineers and
scientists are looking into the methods of bringing comfort to the people while
at home and at work. They produced an
appliance to help produce a cooler temperature for individuals known as AIR
CONDITIONER. This appliance has been in
operation for a very long time but most users prefer dumping their old ones for
new Air conditioner due to lack of knowledge on how to maintain, repair or even
rehabilitate minor faults in an air conditioner.
1.2 LITERATURE REVIEW
The origin
of an air conditioner is necessary to trace.
Its original conception, and the people that were involved in its
production at its initial state.
An air
conditioner was gradually developed and produced for cooling, cleaning heating and facilitating ventilating
processes such as:
The end of
the 15th century, Leonardo da rinci had built the first ventilating
fan.
In
the year 1959, Boyle and also in the year 1800, Dalton discovered both discovered laws for
ideal gases.
In 1815
Robertson Buchanan published the first book on heating and ventilation.
In the
middle of the 19th century fans, boilers and radiators had been
invented.
In 1834,
Alexander Twinning started commercial production of water ice, using the
compression pump and sulphuric either as refrigerant.
Second half
of 19th century, brought about the further development of ice making
and air conditioning processes.
In the 20th
century, Willis H. Carrier who is known as the “Father of Air Conditioningâ€
designed and installed the first year round air conditioning system. It was performing the four major functions of
heating, cooling, humidifying and dehumidifying of the air or rather using the
air washer.
Willis
H. Carrier (1976 – 1950) developed the applications of a forced draft fans,
pipe coil heaters, centrifugal compressors, invented a psychometric chart and
generally laid down the theory of air conditioning on a complete thermodynamic
basis. On the most famous paper
“Regional psychometric formulae†published in the year 1911, Willis Carrier
related the dry bulb, we bulb; dew point temperatures of air with its sensible,
latent and total heat and presented a theory adiabatic chart.
Air
conditioning was increasingly been in use after Willis carrier’s invention; in
cotton, rayon, silk, paper, tobacco,
cady pharmaceutical and printing industries all around the world.
The first
comfort for the people the air-conditioning was first installed in cinema
building in 1920 in Chicago,
employing dry ice machine and in 1922 in Los – Angeles using ammonia
compressors.
This
brought about an increase in demand and expansion in air conditioning
equipments sales to cinema, office building, hostels, hospitals, airport
terminal, departmental stores, banks, shops, and individual homes etc in the
market, the buyers were assumed of better packages than the earlier ones.
1.3 WHAT IS
AN AIR CONDITIONER
The
provision of it can be defined as the process of treating air in order to clean
or purify it, to control its temperature and humidity by heating or cooling and
by humidifying and dehumidifying and to supply sufficient outdoor air for
ventilation. The word air conditioning
is employed to any process or system which fulfil all these requirements.
1.4 WHY WE
USE AIR CONDITIONER
1.
According
to science, oxygen is needed for human life and for any living thing to stay
alive, is one of the vital use of an air conditioner.
2.
Air
acts as a dilatants; ie the amount of air required depends on the permissible
contaminant level for the room. The
contaminant may be C02 human skin or omission from any other
processes.
3.
The
air condition promotes air movement in t he space; this brings one of the
environment comfort factors.
4.
An
air conditioner controls air borne contamination i.e industrial ventilation.
1.5 SIGNIFICANCE OF STUDY
The purpose of studying about Air – conditioner is to show how necessary it is needed
in a house. In other words, when one
owns this appliance and its not functioning properly due to a faulty in the
system, this study is very important and a guide to the relevant steps of
maintaining and knowing what one should do in order to discover a fault in the
air conditioner and having a solution.
1.6 LIMITATION OF STUDY
We are expected to explore all avenues and ways of
finding the simple and adequate procedures in repairing the Air conditioner
given to us, our study without any exception or delineated areas are left out.
Proper maintenance of all types of air
conditioner is the basis of our study.
1.7 BASIC COMPONENTS OF AN AIR CONDITIONER
The air conditioning system has four
basic component parts. These are as
follows:
1.
Compressor
2.
Condenser
3.
Metering
device
4.
Evaporator
Furthermore, there are other
components as follows:
1.
Fan
motor
2.
Fan
blade
3.
Over
load
4.
Relay
5.
Drier
strainer
6.
Thermostat
7.
Flexible
cable
8.
Air
conditioning junction box
9.
Bulb
10.
Fiber
(lagging) material
11.
Switch
12.
The
working fluid (refrigerant)
13.
Back
cover (Hide)
14.
Capacitor
15.
Filter
16.
Grile
17.
Fan
Blower
18.
Capillary
1.8 FUNCTIONS OF THE COMPONENTS
COMPRESSOR: The
compressor can be explained as the heart of mechanical air conditioning system.
The compressor pumps the refrigerant
gas throughout the entire system. It
draws cool refrigerant gas through the suction line from the gas there by
raising the pressure and temperature and then pumps it into the discharge line.
There are various types of compressor
namely:
1.
Rotary
compressor
2.
Reciprocating
compressor
3.
Centrifugal
compressor
4.
Screw
compressor.
THE CONDENSER: The condenser is a component in
the air conditioner, which transfers heat from air conditioning system to a
medium where they can be absorbed and moves it to the final disposal point.
The condenser is the channel through
which unwanted heat is liberated out of the air conditioning system. It is the condenser that superheated high
pressured refrigerant vapour is cooled to its boiling (conferring) point by rejecting
sensible heat. The additional rejection
of latent heat causes the vapour to condense to the liquid state.
TYPES OF CONDENSER
1.
Water
cooled shell and cool condenser
2.
Water
cooled shell and tube condenser
3.
Air
cooled condenser
4.
Evaporative
condenser.
THE EVAPORATOR
The evaporator is a device in the low
pressure side of an air conditioning system through which an unwanted heat
flows. The evaporator absorbs the heat
into system in order that it may be moved or transferred to the condenser. The evaporator is also known as a “coolingâ€
blower cool, “Chilling unit “.
Its ultimate function is to absorb
heat from the surrounding air or liquid and by means of refrigerant the heat is
carried along out of the air-conditioned areas.
TYEPS OF EVAPORATOR
1.
Shell
and tube direct expansion evaporator
2.
Shell
and tube flooded evaporator
3.
Submerged
coil evaporator
4.
Boud
lot/coolers.
OTHER COMPONENTS
AND THEIR FUNCTIONS
DRIER/STRAINER: This
serves as the filter for the filtration of the refrigerant gas, also small
amount of heat reduction takes place in it.
OVER LOAD AND
RELAY: These are sensitive materials
inside the air conditioner, they serve the purpose of protecting the compressor
by tripping off any unwanted current coming into the compressor thereby
preventing damage to compressors.
THERMOSTAT: This can be explained as when the air conditioner
attains its maximum cooling point, the thermostat will cut off current; also,
it trips off the compressor when the voltage is low.
FLEXIBLE CABLES: Flexible
cables are their copper wire that supplies current from the power source with
the help of plug to the air conditioner.
BULB: Bulb
is a power indicator, it lights up when the current has entered the air
conditioning system.
FOAM THAT COVERS
THE INTERNAL BODY: This
is a substance which covers the in cover of the air conditioner so as to avoid
loss of cool air or escape of cooled air that comes from the evaporator.
SWITCH: The
switch controls the current coming into the air conditioning system; that is,
it is the key which opens and closes (on and off) the activities of the air
conditioner.
FRONT GRILLE: Front grille is used to cover the front part of an
air conditioner in other to prevent damages to other components a round it.
FAN MOTORS: It
is known as the unit in between the fan blade and the fan blower where the current
is produced to drive the fan blade and fan blower.
FAN BLADE: The
fan blade is located at the back of the condenser. It blows away hot air from the room.
FAN BLOWER: This
can be located at the back of the evaporator system. It blows cool air from the system into the
room.
FILTERS: This
is an instrument that filters the air in other to prevent the dust in the air
from entering the evaporator.
CAPACITOR: The
capacitor is a unit used to charge and draw more current; it is also used for
starting period in maintaining the lowest mark of change in temperature from
hot to cold.
CAPILLARY
TUBE/METERING DEVICE: This device is carefully
calibrated in length and inside diameter to meet the exact amount of liquid
refrigerant flow required for each unit.
FIBER (LAGGING)
MATERIAL: This material is mostly made of
wool and it is used to prevent the loss of heat in order to maintain the
temperature of the air conditioner.
1.9 AIR CONDITIONING SYSTEM/THE PROPERTIES OF
AIR
Air is the medium at which an air conditioner works,
before we cool or heat it, we have to condition it first; by so doing, it cools
or heats a building and makes it s occupants comfortable.
An air conditioning is the complete
conditioning of air by heating, cooling, humidifying, dehumidifying, filtering,
cleaning and distribution.
All the systems do not require the induction of all these
conditioning processes, but each system requires consideration of all the
processes. The atmospheric air is
composed of (i) Dry air (ii) Moisture in the form of water vapour or s team
(iii) impurities such as smoke, dust and toxic gases.
Pure dry air is a moisture of several
gases like oxygen, nitrogen and varying amount of carbon (iv) oxide and the
inert gases.
Get the Complete Project Material Now!!!
