2. 2
•Sistem Indirect Expansion –menggunakan medium lain untuk
penghantaran udara dingin melalui konsep pemindahan haba.
Digunakan pada sistem berkapasiti besar dan luas. Sistem
Penyejukan Berpusat Sistem District Cooling
• Sistem Direct Expansion (DX system) – hanya menggunakan
bahan dingin sebagai agen penyejuk terus kepada pengguna .
Digunakan pada sistem berkapasiti kecil (domestik)
1.Split Unit
2.Window Unit
PENGENALAN SISTEM UNIT CHILLER
3. 3
• Sistem Penyejukan berpusat dan sistem District Cooling
merupakan proses kitaran pendinginan udara pada satu
lokasi yang kemudian diagihkan kepada semua arah atau
lokasi yang lain.
• Sistem ini memiliki beberapa komponen utama iaitu unit
penyejuk atau Chiller, Air Handling Unit (AHU), menara
pendinginan, sistem pam, sistem perpaipan, sistem saluran
udara atau ducting dan sistem kawalan operasi.
PENGENALAN SISTEM UNIT CHILLER
6. CHILLER UNIT
(Unit Penyejuk)
Dalam kebanyakan aplikasi penghawa dingin, unit
penyejuk diperlukan untuk menghasilkan air dingin
untuk gegelung penyejukan.
Haba yang dikeluarkan daripada air dingin dalam
bahagian penyejat dipindahkan melalui bahan
dingin ke pemeluwap, di mana haba kemudian
diserapkan kepada air sejuk.
6
7. CHILLER UNIT
(Unit Penyejuk)
Penyejat dan pemeluwap direka sebagai penukar
haba untuk menolak haba ATAU untuk
menyerap haba dari sistem air.
Pemeluwap penyejukan air biasanya disejukkan
dengan membebaskan haba ke atmosfera
dalam menara pendinginan sebelum dikitar
semula untuk unit penyejuk.
Pemampat jenis empar, salingan atau
skru digunakan untuk memampatkan gas bahan dingin.
Ia boleh dipacu oleh sebuah motor samada melalui
penjanaan kuasa elektrik atau kuasa haba melalui turbin
pembakaran bahan api diesel /gas asli.
7
12. Jenis Bahan Dingin
12
Pressure Old Current New design
Low CFC-11 HCFC-123 HCFC-123
HFC-245fa
Medium CFC-12 HCFC-134a HFC-134a
HC
High HCFC-22 HFC-407 HFC-407C
HFC-410A
HC
16. JENIS – JENIS PENYEJAT SISTEM CHILLER
16
Brazed plate evaporator /
Kepingan penyejat.
Shell in tube
evaporator/ tiub dalam
sangkar
Shell and Coil
evaporator / Gelung
dalam sangkar
17. JENIS – JENIS PEMELUWAP SISTEM CHILLER
17
Pemeluwap Gelung
Dalam Sangkar
Pemeluwap kepingan
Pemeluwap Tiub Dalam
Sangkar
Pemeluwap Tiub Dalam
Tiub
18. JENIS – JENIS PENYEJUKAN PEMELUWAP
SISTEM CHILLER
AIR COOLED CHILLER ( CHILLER SEJUKAN – UDARA)
WATER COOLED CHILLER ( CHILLER SEJUKAN - AIR)
EVAPORATIVE COOLED CHILLER ( CHILLER AIR –
UDARA )
18
19. JENIS – JENIS PENYEJUKAN PEMELUWAP
SISTEM CHILLER
19
water-cooled (sejuk – air)
air-cooled (sejuk udara)
Evaporative – Cooled
(pemeluwap – Cairwapan )
22. Penyelenggaran Sistem Chiller/ Sejukkan Air
dan Sejukkan Udara
Condenser tube brushing/
Memberus paip pemeluwap
Tower maintenance/
Penyelanggaran menara pedingin
Makeup water/ Air Tambahan
Water treatment/ Rawatan air.
22
Cooling Tower/ Menara PendinginCooling Tower/ Menara Pendingin
23. Penyelengaraan
Penyelenggaran adalah sebahagian kerja dan
tugas seorang mekanik atau juruteknik dalam
penyejukan dan penyamanan udara.
Jenis – jenis penyelenggaraan ialah :
Penyelenggaran berkala/ Routine
maintenance/ Periodic maintenance
Penyelenggaran mencegah/
Prevantive maintenance
Penyelenggaraan Luar
Jangkaan/Breakdown / Force
maintenance
23
24. Tujuan penyelengaraan
a) Memastikan sistem sentiasa beroperasi pada tahap
keupayaan yang sebenar
b) Membantu memanjangkan jangka hayat
komponen-kompenen pada sistem.
c) Menentukan sistem tidak mudah ditimpa masalah
dan kerosakan dan kerosakan semasa beroperasi.
24
25. 25Kerja-kerja Penyelengaraan
• Kerja ini hendaklah dibuat dengan meliputi
setiap aspek.
• Penyelenggaraan haruslah dibuat mengikut
aturan dan sistemetik.
1) Kerja penyelenggaraan yang baik
membantu mekanik itu sendiri pada masa
akan datang dalam menyelesaikan tugasnya.
2) Penyelenggaraan keatas sistem adalah
melibatkan kerja-kerja berikut :-
a) Pembersihan dan servis
b) Pemeriksaan.
c) Rekod dan laporan.
26. Pembersihan dan servis
Kerja – kerja pembersihan dan servis adalah:-
Membersih dan memcuci penapis udara.
Membersih dan memcuci fin pada gegelung penyejat
Membersih dan mencuci gegelung pemeluwap
Membersih saluran paip air bangunan
Membersih keseluruhan bahagian lua unit.
Membersih bahagian takungan air di menara pendingin
Membuat pelincran(Greasing) pada bearing.
Mengetat skru, Bolt dan Nat yang longgar.
Membersih papan suis dan litar penghidup dari habuk.
Mengetat skru pengikat pada setiap terminal pendawaian.
26
27. Operation & Maintenance Schedule
Maintenance Overall system Chiller and cooling towers AHU Filters
replacement
Daily ~ Log chiller temp, pressure, operations
~ Check water treatment
Weekly ~ Check refrigerant and oil change
Monthly ~ Inspect all units
~ Check filters, change if
necessary
~ Flat Panel
Quarterly
(every 3
month)
~ Check purge and Operation ~ 2” Pleated
Semi-Anually
(every 6
month)
~ Lubricate fan motor
andd bearings
~ Check fan belt tension
~ Clean oils
~ Calibrate pneumatics
controls
~ Check compressor oil, filter elements.
~ Check and clean oil return system
~ Check safety and cut-outs
Anually
(every 12
month)
~ Tighten screws
~ Clean fan and casings
~ Lubricate damper
linkage and verify
operation
~ Verify operation of
control system
~ Replace oil
~ Inspect and clean strainers, tubes and cooling towers
~ Inspect tubes and sheets.
~ Service motors (clean air passage and windings, lubricate)
~ Clean purge valves and orifices
~ Inspect and service electrical components
~ Vibration analysis
~ 4” pleated
~ 6” – 12”
cartridge
27
28. 28
•Compressor oil
• Ambil bacaan aras minyak dan warna minyak
•Refrigaration sistem
• Ambil Bacaan tekanan gas
• Control System
• Ambil bacaan current (amp) pada sistem dan
periksa switch board
• Machine Operation
•Water Pumps and Motor
Ambil Bacaan
29. Merekod Laporan Pemerikasaan
Setiap kriteria pemeriksaan yang dijalankan samada
pada arus, suhu dan tekanan hendaklah direkod
pada borang laporan servis dari sinilah analisa
keputusan dapat dibuat.
Dalam keadaan yang tertentu, keputusan yang
tepat hendaklah dapat dibuat setelah dianalisa
bacaan arus, suhu dan tekanan.
Elakan dari membuat keputusan melalui satu
bacaan sahaja.
SPU4033LA03PenyelanggaranUnitPenyamananUdara
Industri-ChillerUnit
29
30. RUMUSAN
Cara – cara penyelanggaran bergantung kepada jenis-
jenis chiller yang digunakan.
Setiap unit penyejukan chiller perlu ada kad
penyelanggaran bagi memastikan sesuatu unit itu
beroperasi dengan sempurna. Kad penyelanggaraan ini
juga dapat menentukan samada sesuatu unit itu masih
boleh digunakan atau sebaliknya.
30
Hinweis der Redaktion
Pensyarah mengalukan kehadiran pelajar
Pensyarah menerangkan berkenaan peraturan berkaitan dengan PdP
Kehadiran
Penilaian
Komitmen dalam kelas
Pensyarah menerangkan hasil pembelajaran yang akan dicapai oleh pelajar di akhir topik.
Pensyarah perlu menerangkan sistem yang hampir sama seperti sistem water cooled pakage/ air cooled pakage
Pelajar memberi respon terhadap sistem yang serupa..
Pensyarah menerangkan hasil pembelajaran yang akan dicapai oleh pelajar di akhir topik.
Pensyarah perlu menerangkan sistem yang hampir sama seperti sistem water cooled pakage/ air cooled pakage
Pelajar memberi respon terhadap sistem yang serupa..
Pensyarah menerangkan kitaran sistem penyejukan chiller dan memberi contoh pengunaannya
Pensyarah menerangkan kitaran sistem penyejukan chiller dan memberi contoh pengunaannya
Sila rujuk gambarajah selepas muka suarat ini.
Sila rujuk gambarajah selepas muka suarat ini.
Pensyarah diminta untuk menerangkan perubahan suhu yang berlaku terhadap sistem
Pensyarah dan pelajar berbingcang terhadap gambarajah di atas.
Pensyarah diminta supaya menerangkan lebih lanjut aplikasi penggunaannya seperti gambarajah diatas.
The refrigeration cycle is a key differentiating characteristic between chiller types. The vapor-compression and absorption refrigeration cycles are the two most common cycles used in commercial air conditioning.
Water chillers using the vapor-compression refrigeration cycle vary by the type of compressor used. Reciprocating, scroll, helical-rotary, and centrifugal compressors are common types of compressors used in vapor-compression water chillers.
Absorption water chillers make use of the absorption refrigeration cycle.
When comparing air-cooled and water-cooled chillers, available capacity is the first distinguishing characteristic. Air-cooled chillers are typically available in packaged chillers ranging from 7.5 to 500 tons [25 to 1,580 kW]. Packaged water-cooled chillers are typically available from 10 to 3,000 tons [35 to 10,500 kW].
Pensyarah menerangkan tentang jenis bahan pendinding yang dipakai oleh sesuatu sistem. Ianya bergantung kepada jenis modul pengeluar yang digunakan.
Pensyarah menerangkan kitaran asas penyamanan udara dalam sistem chiller.
Pensyarah menerangkan jenis – jenis chiller dan jenis chiller yang biasa digunakan.
The type of compressor used generally has the greatest impact on the efficiency and reliability of a vapor-compression water chiller. The improvement of compressor designs and the development of new compressor technologies have led to more efficient and more reliable water chillers.
The reciprocating compressor was the workhorse of the small chiller market for many years. It was typically available in capacities up to 100 tons [350 kW]. Multiple compressors were often installed in a single chiller to provide chiller capacities of up to 200 tons [700 kW].
Scroll compressors have emerged as a popular alternative to reciprocating compressors, and are generally available in hermetic configurations in capacities up to 15 tons [53 kW] for use in water chillers. As with reciprocating compressors, multiple scroll compressors are often used in a single chiller to meet larger capacities. In general, scroll compressors are 10 to 15 percent more efficient than reciprocating compressors and have proven to be very reliable, primarily because they have approximately 60 percent fewer moving parts than reciprocating compressors. Reciprocating and scroll compressors are typically used in smaller water chillers, those less than 200 tons [700 kW].
Helical-rotary (or screw) compressors have been used for many years in air compression and low-temperature-refrigeration applications. They are now widely used in medium-sized water chillers, 50 to 500 tons [175 to 1,750 kW]. Like the scroll compressor, helical-rotary compressors have a reliability advantage due to fewer moving parts, as well as better efficiency than reciprocating compressors.
Centrifugal compressors have long been used in larger water chillers. High efficiency, superior reliability, reduced sound levels, and relatively low cost have contributed to the popularity of the centrifugal chiller. Centrifugal compressors are generally available in prefabricated chillers from 100 to 3,000 tons [350 to 10,500 kW], and up to 8,500 tons [30,000 kW] as built-up machines.
These various types of compressors are discussed in detail in the Refrigeration Compressors Air Conditioning Clinic.
Pensyarah menerangkan kelebihan sistem dan cara menyelanggara penyejat.
Air-Cooled or Water-Cooled Condensing
The heat exchangers in the water chiller (the condenser and evaporator) have the second greatest impact on chiller efficiency and cost. One of the most distinctive differences in chiller heat exchangers continues to be the type of condenser selected—air-cooled versus water-cooled.
Packaged or Split Components
Water-cooled chillers are rarely installed with separable components. Air-cooled chillers, however, offer the flexibility of separating the components in different physical locations. This flexibility allows the system design engineer to place the components where they best serve the available space, acoustic, and maintenance requirements of the customer.
A packaged air-cooled chiller has all of the refrigeration components (compressor, condenser, expansion device, and evaporator) located outdoors. A major advantage of this configuration is factory assembly and testing of all chiller components, including the wiring, refrigerant piping, and controls. This eliminates field labor and often results in faster installation and improved system reliability. Additionally, all noise-generating components (compressors and condenser fans) are located outdoors, easing indoor noise concerns. Finally, indoor equipment-room space requirements are minimized.
The conventional chilled-water system consists of combinations of the following primary components:
Water chillers
Load terminals (chilled-water cooling coils in comfort-cooling applications)
Cooling towers in water-cooled systems
Chilled- and condenser-water pumps
Chilled- and condenser-water distribution systems that include piping, an expansion tank, control valves, check valves, strainers, and so forth.
A major advantage of using an air-cooled chiller is the elimination of the cooling tower. This eliminates the concerns and maintenance requirements associated with water treatment, chiller condenser-tube cleaning, tower mechanical maintenance, freeze protection, and the availability and quality of makeup water. This reduced maintenance requirement is particularly attractive to building owners because it can substantially reduce operating costs.
Systems that use an open cooling tower must have a water treatment program. Lack of tower-water treatment results in contaminants such as bacteria and algae. Fouled or corroded tubes can reduce chiller efficiency and lead to premature equipment failure.
Trainer provides a recap of the Element asking questions to check student understanding and responding to questions from students, as required.
Trainer thanks students for their attention and encourages them to apply course content in their workplace activities.
