‘I admit that I have read this report and in my opinion this report is fulfilled the scope and quality for award condition of Bachelor of Mechanical Engineering (Thermal-Fluids)’
STUDY ON PREDICTIVE MAINTENANCE OF HVAC SYSTEM
AHMAD BIN ISMAIL
This report was adduced in partial fulfillment for award condition of Bachelor of Mechanical Engineering (Thermal-Fluids)
Faculty of Mechanical Engineering Universiti Teknikal Malaysia Melaka
ii
“I hereby, declare this report is the result of my own research except as cited in the references”
Signatures :……….
Author ‘s Name:……….
iii
Special Thanks To My Beloved Parents, Ismail and Zainab… My Whole Family,
Abang Ki, Kak Na and Family Kak Yah, Abang Yie and Family
Abang Wi Abang Ha Adik Mil
And All My Beloved Friends and Lecturers at UTeM For All Your Commitments and Supports
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ACKNOWLEDGEMENT
Alhamdulillah, after all the effort of work and studies, this report of Projek Sarjana Muda (PSM) has finally completed. This one year of the PSM is able to complete within the time frame with the help of some of the people who have willingly to shared knowledge, ideas and lend their hand to me while completing this research. Therefore, I would like to take this opportunity to express my token of appreciation to those who have directly or indirectly involved in this project.
Firstly, I would like to thank both of my parents for their support upon completing this project. My deepest thank goes to my supervisor, Mr. Ahmad Fuad. Thank you very much for sharing his expertise knowledge, thoughts and ideas with me. Thanks for all the guidance he have given to me. Without his guidance and advice, I would not be able to perform my research project.
A token of appreciation also goes to all JKR staffs at Mechanical Department especially to Mr. Zainal as Head of Maintenance Unit (Building Services) and also Mr. Masri as JKR Technician at Seri Negeri. Not forgotten also to all my friends and all my fellow course mates in making this PSM a success. Thank you for their time, knowledge and skill for helping me in terms of ideas, transportation, facilities, financial, etc.
v
ABSTRACT
vi
ABSTRAK
vii
TABLE OF CONTENTS
CHAPTER ITEMS PAGES
CONFESSION ii
DEDICATION iii
ACKNOWLEDGEMENT iv
ABSTRACT v
ABSTRAK vi
TABLE OF CONTENTS vii
LIST OF TABLES xi
LIST OF FIGURES xii
LIST OF ABBREVIATIONS, SYMBOLS &
UNIT xv
LIST OF APPENDIXES xviii
CHAPTER 1 INTRODUCTION 1
1.1 Background 1
1.2 Objectives 2
1.3 Problem Statements 2
1.4 Scope 3
CHAPTER 2 THEORY 4
2.1 HVAC System 5
viii
CHAPTER ITEMS PAGES
2.2.1 Heating 6
2.2.2 Ventilating 9
2.2.3 Air Conditioning 10
2.3 Central HVAC System Components 11
2.4 How an HVAC Works 13
CHAPTER 3 LITERATURE REVIEW 16
3.1 Wireless Condition Monitoring and Maintenance for Rooftop Packaged Heating, Ventilating and Air-Conditioning by Katipamula, S. and Brambley, M. R 16
3.1.1 Monitoring Plan, Automated Fault Detection and Diagnostics 17
3.1.2 Costs of Package-Unit Monitoring Systems 22
3.2 Improved Thermal Building Management with the Aid of Integrated Dynamic HVAC Simulation by Mathews, E.H. and Botha, C.P. 26 3.2.1 Case Study 26
3.2.2 Improved Building Management Through Simulation 28
3.2.2.1 Cooling Coil Fouling 28
3.2.2.2 Chiller Degradation 30
3.2.2.3 Control Strategy Adjustment 32
3.3 Model-Based Fault Detection and Diagnosis of HVAC Systems Using Support Vector Machine Method by Liang, J. and Du, R 35
3.3.1 Design of MBFDD Scheme 35
ix
CHAPTER ITEMS PAGES
3.3.3 Fault Diagnosis Results 38
CHAPTER 4 METHODOLGY 40
4.1 Do Research By Articles, Journals,
Reference Books, Etc. 42 4.2 Identify Problems Statements 42 4.3 Identify Systems Used 42 4.4 Find the Place to Do Research 43 4.5 Make Observation Research and Interview 43 4.6 Make on Documentation Research 43 4.7 Make Analysis and Discussion 44
CHAPTER 5 RESULT 45
5.1 Common Problems Occurred 46 5.2 Predictive Maintenance (PdM) on Chiller 48 5.3 Predictive Maintenance (PdM) on Air
Handling Unit (AHU) 48
5.4 Vibration Analysis 48
5.5 Oil Analysis 51
5.6 Building Automation System (BAS) 52
CHAPTER 6 DISCUSSION 56
6.1 Advantages and Disadvantages of Predictive
Maintenance 56
6.2 Others Predictive Maintenance Technologies 59
6.2.1 Eddy Current Testing 59
6.2.2 IR Thermography 60
6.2.3 Ultrasonics Testing 62
x
CHAPTER ITEMS PAGES
6.3 The Costs of Condition Monitoring
Technologies 64
CHAPTER 7 CONCLUSION 66
xi
LIST OF TABLES
NO. TITLE PAGES
3.1 Costs for a Wired System for Monitoring Six HVAC Units
(Source: Katipamula and Brambley, 2004) 23 3.2 Costs for a Low-Cost Wireless System for
Monitoring HVAC Units
(Source: Katipamula and Brambley, 2004) 25 3.3 Simulated indoor (return) temperatures of
lecture rooms when heatingelements are disabled due to coil fouling. (The shaded area indicates the rooms that are unoccupied.)
(Source: Mathews and Botha, 2003) 34
6.1 Advantages and Disadvantages of Predictive Maintenance 58
6.2 Approximate Costs to Start CBM in Various Technologies
xii
LIST OF FIGURES
NO. TITLE PAGES
2.1 Boiler
(Source: Internet reference, 23/08/2008) 7
2.2 Furnaces
(Source: Internet reference, 23/08/2008) 8 2.3 Heating coils
(Source: Internet reference, 23/08/2008) 9 3.1 Schematic of Condition Monitoring System
for Rooftop Packaged Units with Wireless Sensors
(Source: Katipamula and Brambley, 2004) 18 3.2 Schematic Depiction of HVAC and Monitoring
Equipment Layout
(Source: Katipamula and Brambley, 2004) 22 3.3 Prototype Integrated Wireless Data Collection
and Transmission Unit
(Source: Katipamula and Brambley, 2004) 24
3.4 Schematic layout of the chilled water HVAC system
installed in the case study building
(Source: Mathews and Botha, 2003) 27
3.5 Simulated effect of reduced cooling coil efficiency
on indoor temperatures in the building
xiii
NO. TITLE PAGES
3.6 Simulated effect of reduced cooling coil
efficiency on chiller power consumption
(Source: Mathews and Botha, 2003) 30
3.7 Simulated effect of reduced chiller efficiency
on indoor temperatures in the building
(Source: Mathews and Botha, 2003) 31
3.8 Simulated effect of reduced chiller efficiency
on chiller power consumption
(Source: Mathews and Botha, 2003) 32
3.9 Schematic layout of the air flow through the
reheating system currently used in the case study building
(Source: Mathews and Botha, 2003) 33 3.10 The block diagram of the MBFDD method
(Source: Liang and Du, 2006) 34 3.11 Illustration of a single zone HVAC system model
(Source: Liang and Du, 2006) 36 3.12 Design of the SVM classifier
(Source: Liang and Du, 2006) 38 3.13 Flow chart of the four-layer SVM classifier
(Source: Liang and Du, 2006) 39 4.1 Flow Chart of Research Procedure 41
5.1 Chiller 45
5.2 AHU 45
5.3 Typical Vibration Transducers
(Source: www.eere.energy.gov/femp, 27/03/2009) 49 5.4 Typical Hand-held Vibration Sensing Meters
xiv
NO. TITLE PAGES
5.5 Typical Vibration Analyzer
(Source: www.eere.energy.gov/femp, 27/03/2009) 50 5.6 Oil Analysis Work and Typical Oil Analysis Equipment
(Source: Carrier Corp., 2002) 52 5.7 Chiller Plant Diagram
(Source: JKR, 2009) 54
5.8 DDC Controller Panel 55
6.1 Doing Eddy Current Testing
(Source: Carrier Corp., 2002) 59 6.2 Example Thermogram Showing Misalignment
(Source: www.eere.energy.gov/femp, 27/03/2009) 61 6.3 Typical IR Spot Thermometer
xv
LIST OF ABBREVIATIONS, SYMBOLS & UNIT
HVAC Heating, Ventilating and Air Conditioning IAQ Indoor Air Quality
ASHRAE American Society of Heating, Refrigerating and Air Conditioning Engineers
% Percentage
°F Fahrenheit Degree LPG Liquid Petroleum Gas cfm cubic feet per minute OA Outside Air
MUA Make-up air fpm feet per minute CT Cooling Tower
CWP Condenser Water Pump CWS Condenser Water Supply CWR Condenser Water Return CH Chiller
CHWP Chilled Water Pump CHWS Chilled Water Supply CHWR Chilled Water Return CC Cooling Coil
HC Heating Coil
xvi
HHWS Heating Hot Water Supply B Boiler
SAF Supply Air Fan
SAD Supply Air Duct
MVD Manual Volume Damper
CD Ceiling Diffuser
RA Return Air Inlet
RAF Return Air Fan
RA Return Air Dampers
ATC Automatic Temperature Control Damper
EA Exhaust Air (Dampers)
F Filters
ATC Automatic Temperature Control Valve
MBV Manual Balancing Valve
AHU Air Handling Unit
RTU Roof Top Unit
Btu/hr British thermal unit per Hour
MVD Manual Volume Dampers
TR Ton of Refrigeration
FDD Fault Detection and Diagnostic
m2 meter square
mm milimeter
FCU Fan Coil Units
COP Coefficient of Performance
MBFDD Model-Based Fault Detection and Diagnosis
SVM Support Vector Machine
SMO Sequential Minimal Optimization
Hz Hertz
AC Alternating Current
DC Direct Current
xvii
PM Preventive Maintenance
PdM Predictive Maintenance
PaM Proactive Maintenance
FBM Failure Based Maintenance BAS Building Automation System DDC Direct Digital Control
CBM Condition Based Monitoring MCSA Motor Current Signature Analysis
IR Infrared
FAM Facilities and Asset Management
xviii
LIST OF APPENDIXES
NUM. TITLE PAGES
A Gantt Chart 70
B Carrier Hermetic Screw Liquid Chiller 71
1
CHAPTER 1
INTRODUCTION
1.1 Background
2
1.2 Objectives
While doing this study or research, they are some objectives that should be achieved based on problems that we want to encounter. The objectives are to:
i. Identify the problems that commonly occurred on the HVAC system.
ii. Study the predictive maintenance or condition monitoring of the HVAC system iii. Analyze the advantages and disadvantages by using condition monitoring on
HVAC maintenance.
1.3 Problem Statements
3
1.4 Scope
4
CHAPTER 2
THEORY
5
2.1 HVAC System
Commercial heating, ventilating and air conditioning (HVAC) systems provide the people working inside buildings with conditioned air so that they will have a comfortable and safe work environment. People respond to their work environment in many ways and many factors affects their health, attitude and productivity. Air quality and the condition of the air are two very important factors. By conditioned air and good air quality, we mean that air should be clean and odor-free and the temperature, humidity and movement of the air will be within certain acceptable comfort ranges. ASHRAE, the American Society of Heating, Refrigerating and Air Conditioning Engineers, has established standards which outline indoor comfort conditions that are thermally acceptable to 80% or more of a commercial building’s occupants. Generally, these comfort conditions, sometimes called the “comfort zone”, are between 68°F and 75°F for winter and 73°F to 78°F during the summer. Both these ranges are for room air at approximately 50% relative humidity and moving at a slow speed (velocity) of 30 feet per minute or less.
