DCC50252- Notes

CONDENSER

Air-cooling process

Air-cooled Process

In the condensing process, the air (or
water) picks up heat from the refrigerant

In the cooling process, the refrigerant picks
up heat from the room air.

In both instances, a coil is the heat
transfer surface

CONDENSER The condenser
removes enough
A heat exchanged by heat to change the
the where the heat refrigerant from a
vapor to a liquid.
absorb by the refrigerant
is transferred to the
cooler outdoor air or
another cooler
substance

EXPANSION VALVE

The expansion valve removes pressure from the
liquid refrigerant to allow expansion or change of
state from a liquid to a vapor in the evaporator

The thermostatic expansion valve reduces the pressure of the
refrigerant liquid and thus cools the liquid

Refrigerant enters the valve under pressure

As the refrigerant passes through the valve port, it enters the
low-pressure area of the cooling coil

The valve port acts as a metering device between a high-
pressure area ( the condenser) and a low-pressure area (the
cooling coil)
Since the boiling of a liquid is reduced when the pressure of the liquid is reduced, the liquid
refrigerant begins to vaporize once it passes through the valve port into the low-pressure area.

REFRIGERANT

The purpose of the refrigerant is to move heat.

It is the medium by which heat can be
moved into or out of a space or substance

A refrigerant is any fluid ( liquid or gas) that
picks up heat by evaporating at a low
temperature and pressure and gives up heat
by condensing at a higher temperature and
pressure

Refrigerant often boil at very low
temperatures (as low as – 21F)

REFRIGERANT

There is no ideal refrigerant. A refrigerant is said to be ideal if it
has all of the following properties:

Low boiling point Non- flammable and non-explosive
Low freezing point
Non-toxic
High latent heat Non-corrosive
High density
Stable

REFRIGERANT

The refrigerant are classified as follows:

Primary refrigerants Secondary refrigerants

1.Halocarbon compounds. They are sold in the Refrigerants are those circulating substances
market under the names as Freon, Genetron, which are first cooled with the help off the
Isotron and Areton (R11,R12,R21,R22) primary refrigerants and are then employed
for cooling purpose
2.Azeotropes: Consist of mixtures of different These refrigerants cool substances by
substances (R500,R502,R503,R504) absorption of their sensible heat.

3.Hydrocarbons : Most of the refrigerants are The commonly used, secondary refrigerants are:
organic compounds (R50,R170<R600,R600a) i. Water
ii. Sodium chloride brine
4.Inorganic compounds iii. Calcium chloride brine
5.Unsaturated organic compounds

Air-conditioning system

Chapter APPLY THE PROCESS OF THE
4.2 AIR CONDITIONING SYSTEM

4.2.1 4.2.2

Types of air Relate the factors to consider
conditioning system in choosing type of air
conditioning system
01
02

4.2.1. TYPES OF AIR
CONDITIONING
SYSTEM

2

CENTRALIZED UNIT SPLIT UNIT

Central air conditioning (or central A split unit air conditioner is an
A/C) is a system in which air is air conditioning system that
cooled at a central location and consists out of two separate
units; the water or air-cooled
distributed to and from rooms by condensing unit and the air
one or more fans and ductwork handling unit

CENTRALIZED UNIT

Central air conditioners circulate cool air
through a system of supply and return
ducts.
The work of the air conditioner compressor
is what makes the whole process of air
conditioning possible.
There are two types of central air
conditioners:

i.Split system
ii.Packaged unit

1.SPLIT SYSTEM 2. PACKAGE CENTRALIZED
CENTRALIZED UNIT UNIT

This system has an outdoor In these packaged air conditions the
cabinet contains the outdoor condenser is cooled by the water
heat exchanger, fan, and The condenser is of shell and tube type,
compressor, and an indoor with refrigerant flowing along the tube side
cabinet contains the indoor heat and the cooling water flowing along the
exchanger and blower shell side. The water has to be supplied
The indoor cabinet may contain continuously in these systems to maintain
the a furnace or the indoor heat functioning of the air conditioning system.
exchanger of a heat pump The shell and tube type of condenser is
compact in shape and it is enclosed in a
single casing along with the compressor,
expansion valve, and the air handling unit
including the cooling coil or the evaporator

PACKAGE CENTRALIZED UNIT

CENTRALIZED UNIT DISADVANTAGES

ADVANTAGES 1. Expensive
Expensive to install a complete full
1.Cleaner Air comfort air-conditioning system

A central air conditioning system uses filters to help
throughout a building.
improve the quality of your air. This helps eliminate 2.Space for plant room
pollen, dust and lint from the air Space is required for plant and to
run ductwork both vertically in
2.Effective Circulation shafts and horizontally in ceiling
spaces
This type of air conditioning system is the most effective 3.Hard to control
way to circulate cool air through your entire home Individual room control is difficult
with central plant
3.Reduced Noise

Window units make much more noise than central air
conditioners. In comparison, the central system is almost
imperceptible

4.More Space

The central system is located outside of your house. This
creates more space for you inside and keeps your house
looking modern.

5.Easy to Use

From a single control panel, you can set the time and
temperature at which you want the unit to operate .

6. Maintenance

Maintenance is centralized in the plant room. Plant is
easier to access

SPLIT UNIT

A split-system air conditioner splits the hot side from
the cold side of the system, as in the diagram below.
Outdoor unit: The outdoor unit contains a compressor
and a condensing coil filled with refrigerant. A fan
blows outside air over the coil, transferring thermal
energy between the refrigerant and the outside air. The
refrigerant is then circulated through pipes, or line set,
to the indoor unit.
Indoor unit: The indoor unit is made up of a coil and
blower which is located inside of an air handler or
furnace. The blower circulates air through the coil
before it is sent back to the room.

SPLIT UNIT

SPLIT UNIT ADVANTAGES
ADVANTAGES
3.Quiet operation
1.Easy maintenance The split ac units system is very quiet in
The split ac units system should be maintained comparison to other air conditioning systems.
on a regular basis (at least twice a year).This The minimization of noise is importance in rooms
will ensure that it always runs at its optimum which require a peaceful environment
performance levels, in terms of both power and
efficiency.
4. Cost effective
Easily maintained on the basis that they will With regards to the initial cost of purchasing split
normally have a filter which is washable. ac units it may be prudent to note that four indoor
A regular maintenance will also ensure the units can operate from one outdoor unit.
longevity of the split ac units system The running costs of the split ac units are also
cost effective. Split ac units are extremely energy
2.Easier to install efficient.
most of split types can be quickly and easily Energy efficiency ensures that the split ac units
installed. do not work any harder than is ultimately
a window or wall opening is not required to required, thereby minimizing electrical energy
install split ac units. consumption on an on going basis.
The indoor unit can be placed on the floor, hung 5.Simple control
on wall brackets or mounted on the ceiling. The The Split ac units are simple to operate and are
outdoor unit is obviously installed outside of therefore suitable for every and any individual
the buildings. considering the purchase of an air conditioning
system

SPLIT UNIT disADVANTAGES
disADVANTAGES

1.Sometimes the indoor and outdoor 5. Not at robust as central plant.
unit fan becomes noisy.

2.Each unit or group of units has a 6.The majority of room air


filter, compressor and refrigeration conditioners just recirculate air in a
room with no fresh air supply
pipework that needs periodic although most manufacturers make
maintenance and possible re-

charging. units with fresh air capability.
3.Units have course filters therefore 7. Cooling output is limited to about
9 kW maximum per unit; therefore
filtration is not as good as with
AHU’s. many units would be required to

4.The installation may require long cool rooms with high heat gains

runs of refrigerant pipework which,

if it leaks into the building, can be

difficult to remedy.

4.2.2

The factors to consider in choosing type of air conditioning system

EFFICIENCY & COMFORT & TAKING RELIABILITY ENERGY
COST PRACTICALITY CONTROL OF CONSUMPTION
When it comes to
YOUR AC picking a pricier CONCLUSION CONCL
SYSTEM model, it pays to
Choose better AC Select AC system Check the energy
system that suit for with modern Simply install the stick with a efficiency rating,
the space and energy system which MyAir app to your reputable company also known as EER
saving. Cheapest have reverse tablet or mobile rating. The rating
one not necessary is device and have with extensive ranges from 8 to
good, better invest cycle (heat and complete comfort experience and 11.5. The higher the
the good & efficient cold), inverter great after-sales rating, the more
AC for long term use. and smart AC and control energy efficient is
wherever you go service..
the system

THANK YOU

DCC 50252

Air Conditioning
System

Mdm Adilen @ Lucia bt Suil
Lecturer
Dept. of Civil Engineering
POLISAS

CLO 1 : COURSE LEARNING OUTCOME
CLO 2 :
CLO 3 : choose appropriate building services system with consideration of safety
procedures, rules and regulations by the authority

identify building services system with consideration of the
environmental impact
display teamwork in completing a case study of a building services system

4.1 4.2 4.3

DEFINE THE USE OF APPLY THE PROCESS IDENTIFY THE EFFECTS
THE AIR CONDITIONING OF THE AIR OF AIR CONDITIONING
SYSTEM TOWARDS THE
SYSTEM CONDITIONING SYSTEM
ENVIRONMENT

Chapter IDENTIFY THE EFFECTS OF AIR
4.3 CONDITIONING SYSTEM TOWARDS

THE ENVIRONMENT

4.3.1
4.3.2

Identify environmentally Effects of air
friendly air conditioning conditioning gases to

products global warming

4.3.1

IDENTIFY
ENVIRONMENTALLY
FRIENDLY AIR
CONDITIONING
PRODUCTS

What is Environmental Page 06
Friendly?

Environmentally Friendly mean eco-friendly or earth-friendly and
the product or item is not environmentally harmful.
These products promote green living or green manufacturing
methods that lessen the amount or types of resources used.
In short, eco-friendly products help the earth, not cause it harm
Eco-friendly products should indicate on the packaging or
somewhere on the company's website how the products are
environmentally harmless.

Suruhanjaya U.S. International Korea Energy
Tenaga (ST), Environmental Energy Agency
Protection Agency
Malaysia Agency, Australia



GREEN LABEL Environmentally Friendly air
CERTIFICATION conditioning products

What is Page 06
MyHIJAU?

MyHIJAU Mark & Directory is a
Government initiative to promote the
sourcing and purchasing of green
products and services in Malaysia

https://www.myhijau.my/

MEPS

The minimum level of
energy efficiency (MEPS)
which has to be met by
each of applicable air
conditioner

More star, more energy saving

https://www.st.gov.my/en/web/application/details/2/20

EER

EER or Energy-Efficiency Ratio is an
energy performance rating for,
primarily, cooling devices.

A higher EER rating means that an air
conditioner will provide a lot of
cooling effect for every Watt of energy
you provide

EER rating = Capacity (in BTU) / Power (in W)

Example:
A 12,000 BTU mini split air conditioner that is powered by 1000W
ERR = 12,000/1000 = 12
12 EER rating is an excellent energy-efficiency rating for an air conditioner

https://www.st.gov.my/en/web/application/details/2/20

BEST www.reallygreatsite.com
PRODUCT

PANASONIC

Fan motors
Panasonic’s unique motor control technology
automatically adjusts airflow to the optimal output for
all types of construction, resulting in stable ventilation
air volume and energy saving.

Panasonic used nanoe™ Technology purifies the air
Panasonic air conditioner varies from 1Hp to 3Hp

1.0 Hp single split air conditioner (CS-XU10XKH-1 (1.0HP)
Power consumption: 700W
Capacity: 9550 Btu/h
ERR = 9550/700 = 13.64

BEST
PRODUCT

DAIKIN

Daikin specializes in air conditioners
and air purifiers that are energy-
efficient and ozone-friendly

1.0 Hp single split air conditioner
Power consumption: 750W
Capacity: 9700 Btu/h
ERR = 9700/750 = 13

https://www.daikin.com.my/smarto/

BEST
PRODUCT

HITACHI

Hitachi makes all sorts of appliances. And their
air conditioners range from 1HP to 3HP!

Hitachi room air conditioner “Shirokuma-kun” awarded
“FY2019 Energy Conservation Grand Prize” of Japan

1.0 Hp single split air conditioner (RAS-XJ10CKM)
Power consumption: 800W
Capacity: 92100 Btu/h
ERR = 11.51

https://www.hitachiaircon.com/my/

Various Types of Indoor Units

4.3.2

EFFECTS OF AIR
CONDITIONING
GASES TO GLOBAL

WARMING

+123-456-7890

Presentation Design

Does air conditioning
cause global warming?

How to STOP from air
condition heating the planet?

Does air conditioning cause global
warming?

Does air conditioning cause global
warming?

#HFC (hydrofluorocarbons)

Montreal Protocol:

Is an international treaty designed to protect the
zone layer.
A refrigerant is a substance used in a heat cycle
usually including, for enhanced efficiency, a
reversible phase transition from a liquid to a
gas.
Traditionally, fluorocarbons, especially
chlorofluorocarbons (CFC), were used as
refrigerants, but they are being phased out
because of their ozone depletion effects.

Montreal Protocol:

It is highly damaging to the ozone layer, have
been largely eliminated from use: and the
newest ones, used widely in industrialized
nations, have little or no effect on it.
They contribute to global warming thousands of
times more than does carbon dioxide, the
standard greenhouse gas.

Montreal Protocol:

Atmospheric concentrations of the gasses that
replaced CFC, known as HCFC, Hydro
chlorofluorocarbon, which are mildly
damaging to the ozone, are still rising rapidly at
a time when many scientist anticipated they
should have been falling as the treaty is phasing
them out.
Freon is the trade name for CFC’s , used
primarily in refrigeration and air conditioning.

Montreal Protocol:

Freon and other refrigerants are toxic and
can cause poisoning and even death.
Refrigerants service workers are at risk due to
occupational exposure, but exposure most often
occurs during intentionally sniffing the gas.





THANK YOU

DCC50252

BUILDING
SERVICES

Mdm Adilen @ Lucia binti Suil
Lecturer
Civil Engineering Department
POLISAS

Course Learning Outcome

CLO 1 CLO 3

Choose appropriate building Display teamwork in completing
services system with a case study of a building
consideration of safety services system

procedures, rules and regulations 02/27
by the authority.

Ch.5.0

5.0: Maintenance Works

5.1 5.2

Define the concept Explain the
of maintenance maintenance work in
works building

Ch.5.0 03/27

5.1 01 Basic concept of
Define the maintenance works
concept of
maintenance 02 Types of maintenance
works 03 The maintenance schedule

Ch.5.0 04/27

Introduction

Maintenance practices for buildings in Malaysia started
in year 1971.
It became more active in the year 2007 when the Prime
Minister wanted to make maintenance as a new culture
for the whole nation
Its is highly desirable but hardly feasible to produce
buildings that are maintenance-free, although much
can be done at the design stage to reduce the amount
of subsequent maintenance work.
All element of buildings deteriorate at a greater or
lesser rate depending on materials and methods of
construction, environmental conditions and the use of
the building.

Ch.5.0 05/27

Why building deteriorate
(merosot)?

Deteriorate refers to degradation quality building
materials in line with the age of the building
Building failure more like failure structure for example:
movement of soil, deposition of base buildings, design
failure (leaks at the connection wall/floor)
Malfunction of the building system refers to services
does not work, in particular to mechanical/electrical
equipment

Vitelli and Nelson defined defects as failure or malfunction with
good ability, in terms of building guidelines or user needs in the
building that may affect the structure, outline or fabrics,
building services or facilities.

Ch.5.0 06/27

Building's deterioration depends
on FOUR (4) area:

Building's
materials

1

Weather/ 4 Construction
environment 2 methods
conditions
3
Ch.5.0 Building's
use/function

07/27