McQuay MDS030A User manual

Design & Installation Guide For McQuay MDS Multi System
Engineered for flexibility and performance.TM

©2004 McQuay International. All Rights Reserved.
is a registered trademark of McQuay in the United States and other countries, licensed and recognized
all over the world. Without prior written consent of McQuay, use of the above-named trademark for business
purposes may constitute a violation of the federal and state laws in the Unites states and laws of related countries,
and remain subject to a charge of trademark infringement and unfair competition.
This manual is prepared by the Market Department of McQuay ’sShenzhen-based factory. Pursuant to the
copyright law, this manual may not be reproduced or otherwise distributed in whole or in part without prior
written permission of McQuay.
We have used our best endeavor to make sure the information contained in this manual is accurate. As we are
always committed to technological improvement, any change in the units and specifications is subject to further
notice. In addition, to meet local criteria and customer requirements, we may modify the units and specifications.
Please also take notice that not all the models suit every market.
Discussed in this manual is a product made in China in compliance with the national standard –GB/T18837-2002.

CONTENTS
Foreword
1. Overview
1.1 General Information………………………………………………………………………………4
1.2 Working Principle & System Principle…………………………………………………………4
1.3 Main Features……………………………………………………………………………………11
1.4 Nomenclature……………………………………………………………………………………13
1.5 Products Series…………………………………………………………………………………15
1.6 Performance Parameter…………………………………………………………………………16
1.7 Operating Range…………………………………………………………………………………20
1.8 Refnet………………………………………………………………………………………………20
1.9 Outline of Indoor Units…………………………………………………………………………22
1.10 Outline of Outdoor Units………………………………………………………………………28
2. Unit Control
2.1 Introduction of the Controller……………………………………………………………………34
2.2 Main Functions……………………………………………………………………………………34
2.3 Operation of the Controller………………………………………………………………………35
2.4 Software Management System…………………………………………………………………39
2.5 Network Central Control…………………………………………………………………………41
2.6 Wiring Diagram……………………………………………………………………………………42
2.7 Electric Connection………………………………………………………………………………56
2.8 Electric Data……………………………………………………………………………………58
3. Selection
3.1 Load Calculation…………………………………………………………………………………59
3.2 Selection of Indoor Units………………………………………………………………………61
3.3 Selection of Outdoor Units……………………………………………………………………63
3.4 Design of Air System……………………………………………………………………………66
3.5 Selection of Refnet Joint………………………………………………………………………71
4. Installation
4.1 Installation of Indoor Units………………………………………………………………………75
4.2 Installation of Outdoor Units……………………………………………………………………82
4.3 Refrigerant Pipe & Installation…………………………………………………………………87
4.4 Design, Processing and Installation of Condensate Pipe…………………………………102
5. Testing
5.1Hardware Diagram and Equipment………………………………………………… 106
5.2 Running……………………………………………………………………………………………113
6. Servicing and Maintenance
6.1 Notice to the Customer…………………………………………………………………………114
6.2 Maintenance………………………………………………………………………………………115
7. Troubleshooting…………………………………………………………………………………119
Annexes…………………………………………………………………………………………………121

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Design & installation Guide For McQuay MDS Multi System
The MDS(Multi Digital Scroll) air conditioning system is operated by a digital compressor and is
accommodated by multiple evaporators (indoor units). It is touted as the next-generation modular
system in the world of high-efficiency air conditioning. lt has undoubtedly changed the face of cooling
associated with high-storied buildings. It provides a broad range of different applications for settings
such as offices, hotels and schools. With its easy installation and simple controlling system, the MDS
will more than meet the demands of the air conditioning market.
C H A P T E R
1
Overview
1.1 General information
1.2 Working principle & system principle
1.2.1Working principle
The beauty of this technology is its inherent simplicity. The standard digital scroll compressor has
a unique feature called axial compliance. This allows the fixed scroll to move in the axial direction, by
very small amounts, to ensure that the fixed and orbiting scrolls are always loaded together with the
optimal force.
This optimal force holding the 2 scrolls to-
gether at all operating condi tions ensure the
high efficiency of Copeland scrolls. The Digital
Scroll operation builds on this principle.
The Digital Scroll operates in two stages -
the "loaded state", when the solenoid valve is
normally closed and "unloaded state", when
the solenoid valve is open. During the loaded
state the compressor operates like a standard
scroll and delivers full capacity and mass flow.
However, during the unloaded state, there is no capacity and no mass flow through the compressor.
At this stage, let us introduce the concept of a cycle time. A cycle time consists of a "Loaded State"
time and "Unloaded State" time. The duration of these 2-time segments determine the capacity
modulation of the compressor. Example: In a 20 seconds cycle time, if the loaded state time is 10 seconds
and the unloaded state time is 10 seconds, the compressor modulation is (10 seconds x 100% + 10
seconds x 0%)/ 20 = 50% (Figure 3). If for the same cycle time, the loaded state time is 15 seconds
and the unloaded state time is 5 seconds, the compressor modulation is 75%. The capacity is a time
averaged summation of the loaded state and unloaded state. By varying the loaded state time and
unloaded state time, any capacity (10%-100%) can be delivered by the compressor.
fixed scroll
(movable in axial direction)
PWM vale
Orbiting scroll
(Rotatable in radial direction)

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Design & installation Guide For McQuay MDS Multi System
■ PWM valve power off
■ Valve close
■ Fixed scroll move downwards
■ Two scrolls gather together
■ Loading
■ PWM valve power on
■ Valve open
■ Fixed scroll moves upwards
■ Two scrolls separate
■ Unloading
Resident system Commerce system
1.2.2 Installation sketch map

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Design & installation Guide For McQuay MDS Multi System
MDS030AR、MDS040AR、MDS050AR、MDS060AR
1.2.3 System principle
MDS030A、MDS040A、MDS050A、MDS060A
Note: MDS030AR unit excludes the reservoir.
Note: MDS030A unit excludes the reservoir.

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Design & installation Guide For McQuay MDS Multi System
MDS080R、MDS100BR、MDS120BR
MDS150BR

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Design & installation Guide For McQuay MDS Multi System
MDS200BR、MDS220BR、MDS240BR
MDS180BR

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Design & installation Guide For McQuay MDS Multi System
MDS280BR、MDS300BR
MDS260BR

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Design & installation Guide For McQuay MDS Multi System
1.3 Main features
1.3.1 Wide range and stepless capacity modulation
■Wide capacity modulation range（10%-100%)；
■According to changing the ratio of “loading time”and “unloading time, MDS can modulate
the capacity steplessly；
■Lower the energy consumption and running cost.
1.3.2 Accurate temperature control and quick response.
■The cooling/heating capacity of the indoor units is controlled by the EXV,
which ensure the low temperature fluctuation of ±0.3℃;
■Stepless capacity modulation;
■Quick response to output the capacity (40s).
1.3.3 Simple, reliable and long life
■The PWM valve has the longevity of 40 million times
■Wide range of capacity modulation makes sure
the start/stop times reduces
■Less components
■No complicate inverter controller
■The compressor has an excellent oil return
performance, there is no need for the oil return
circuit
■Even the units run in 10% part load, the MDS
system can be in good stage.

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Design & installation Guide For McQuay MDS Multi System
【Note】OT: outdoor unit is above indoor unit; IT: Indoor unit is above outdoor unit
Height Max. accessory Max. accessory Height
pipe length pipe length OT IT
12～30HP 350 150 50 40
10HP 250 125 50 40
8HP 250 125 50 40
6HP 150 70 30 30
5HP 150 70 30 30
4HP 150 70 20 20
3HP 100 50 20 20
1.3.4 Energy saving
■ The inverter system’scapacity modulation range is from 30% to 100%, while MDS system’s
capacity modulation range is from 10% to 100%;
■Quick response to the capacity modulation;
■Min. power consumption is only 10% of the full load power consumption;
■Compared to t he inverter system, there is no power consumption of transducer;
■Compared to the nominal capacity scroll system, it can save 20% energy consumption.
1.3.5 Flexible combination of indoor units
■The max. capacity of the indoor units is as 130% as the outdoor units capacity;
■The outdoor unit can connect different numbers of indoor units according to the outdoor unit
capacity;
■One outdoor unit can be connected up to 48 indoor units;
■Various types of indoor units are available;
■There are various indoor units for option: concealed exposed, ceiling concealed, high static
pressure fan coil and ceiling exposed/floor standing.
1.3.6 Long accessory pipe connection design
■Max. accessory pipe length is 15m (12HP-30HP), max. height is 50m (8HP—0HP).

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Design & installation Guide For McQuay MDS Multi System
1.3.7 Space saving
■Compared to large size central air conditioning, MDS system is high centralized, no need for special
equipment room to save more space, and bring more benefits.
1.3.8 Easy to install and simple to maintain
■Easy installation
●With simple structure, clear piping diagram, little work amount at field installation, MDS system
is equipped with simple indoor and outdoor units and pipe connection, and it is complete with
refrigerant piping system to ease the maintain.
■Independent system, stage installation
●The easy installation makes the users to choose the suitable time to install MDS system
within longer time, which reduces the limits of period to install air conditioning at the installation.
●For new projects, the step installation can decrease the disposal investment.
●For renovation projects, the users can install the units easily.
■No need for special maintenance
●It has only simple refrigerant piping system, no complex maintenance;
●Compared to the chilled water system, MDS system is with no water system, no piping cleaning,
no maintenance for water system control design; and MDS system is much simple so there is no
need for expert people to manage and maintain it.
Traditional central air conditioning MDS system
1.4 Nomenclature
■Indoor unit: ceiling cassette
CK 030 T -- A M A
Design serial No
Cooling capacity No.
Indoor unit: ceiling cassette
McQuay
Design alternation No.
Matching outdoor units:MDS series
Power supply features:220V～/50Hz
M

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Design & installation Guide For McQuay MDS Multi System
■Indoor unit: ceiling concealed unit
■Indoor unit: Ceiling exposed/floor standing unit
M CM 050 T - A M A
Design serial No
Cooling capacity No.
Indoor unit: Ceiling exposed/floor standing unit
McQuay
Design serial No.
Matching outdoor units: MDS series
Power supply features: A:220V～/50Hz
MCC 050 T R (B)/(D) - -A M A
McQuay
Concealed exposed indoor unit
Cooling capacity No.
Design serial No.
Pipe mode:
R-right connecting pipe
L-left connecting pipe
Air return mode:
B-rear air return box
D-lower air return box
Omitted-no air return box
Design serial No.
Matching outdoor units:
MDS series
Power supply features:
A:220V～/50Hz
■Hot water heater box
■Electric heater box
08-15 means it can be used in MCC008/010/015T
18-30 means it can be used in MCC018/020/025/030T
40-50 means it can be used in MCC040/050T
60 means it can be used in MCC060T
T means that unit can be used
in MCC“T”series
Hot water heater box
HW T 08-15
HD P 1.2 T 08-15
18-15 means it can be used in MCC008/010/015T
18-30 means it can be used in MCC018/020/025/030T
40-50 means it can be used in MCC040～050T
60 means it can be used in MCC060T
T means the unit can be used in MCC“T”seres
Heating capacity (kW)
Heating unit: P means the heating unit is PTC Omitted means the
heating unit is electric heating pipe
Electric heater box

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Design & installation Guide For McQuay MDS Multi System
■Air-cooled cooling duct indoor unit
1.5 Products Series
1.5.1 Outdoor unit
Capacity range
3HP 4HP 5HP 6HP 8HP 10HP12HP 15HP 18HP 20HP 22HP 24HP 26HP 28HP 30HP
● ● ● ●
● ● ● ●
● ● ● ● ● ● ●
Model
MDS-A
MDS-B
MDS-B
M DB 050 T - A M A
Design serial No
Cooling capacity No.
Air-cooled cooling duct indoor unit
McQuay
Design serial No.
Matching outdoor units:MDS series
Power supply features: A:220V～/50Hz
■Outdoor unit: MDS unit
MDS 60 A R - F AA
Design serial No
Cooling capacity No
McQuay multi digital scroll unit
Description of the unit
Power supply:
A:220V～/50Hz B:380V/3N～/50Hz
Heat pump (omitted if cooling only)
_________ MEX:Throttle box (one expansion valve)
_________ ominal opening diameter value×10
_________ 2:1/4 inch
_________ 3:3/8 inch
_________ 4:1/2 inch
_________ Flare fitting & nipple joint
_________ Primary design
McQuay
Valve opening size No.
Pipe size:
Pipe mode:
Design serial No.
■MEX throttle box
Design serial No.
Pipe mode
Pipe size:
MEX - 14 - 3 SA - A
McQuay
Valve opening size No.

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Design & installation Guide For McQuay MDS Multi System
1.6 Performance Parameter
1.6.1 Ceiling concealed
Model Indoor MCC MCC MCC MCC MCC MCC MCC MCC MCC MCC
unit 008T 010T 015T 018T 020T 025T 030T 040T 050T 060T
Cooling W2000 2500 3650 4500 5600 6500 7800 10600 12400 14400
capacity
Heating W2200 2600 3700 4700 6100 7400 8900 11600 14500 17300
capacity
Nominal input W 47 47 81 82 82 123 158 276 276 280
Power supply 220V～/50Hz
Air High m3/h 450 450 580 800 800 960 1200 1900 1900 2100
flow Medium m3/h 370 370 470 650 650 780 950 1520 1520 1750
Low m3/h 280 280 380 540 540 600 800 1300 1300 1460
ESP Pa 15(0/30/50) 30(15/50/70) 50(15/30/70)
Dimension mm 1030x469x220 1290x490x250 1640x490x250 1900x490x250
Weight kg 22 22 22 25 25 27 28 39 39 45
Sound(High/ dB (A)
31/29/27 31/29/27 34/32/30 35/32/29 35/32/29 37/36/35 42/40/38 47/45/43 47/45/43 48/46/44
medium/Low)
Piping
Liquid pipe Φ mm(in) 6.35 (1/4) 6.35 (1/4) 6.35 (1/4) 9.52 (3/8) 9.52 (3/8) 9.52(3/8) 9.52(3/8) 9.52(3/8) 9.52(3/8) 9.52(3/8)
size
Gas pipe Φ mm(in) 9.52 (3/8) 9.52 (3/8) 12.7 (1/2) 15.88(5/8) 15.88(5/8) 15.88(5/8) 15.88(5/8) 19.05(3/4) 19.05(3/4) 19.05(3/4)
Drainage pipe inch R3/4
Capacity range
0.8HP 1.0HP 1.5HP 1.8HP 2.0HP 2.5HP 3.0HP 4.0HP 5.0HP 6.0HP
MCC ● ● ● ● ● ● ● ● ● ●
MCK ● ● ● ● ● ● ● ●
MCM ● ● ●
MDB ● ●
Model
1.5.2 Indoor products
Notes:
◆The nominal cooling cap acity is gotten in the return air temperature of 27℃/19℃, and the ambient temperature of 35℃/24℃.
◆The nominal heating capacity is gotten in the return air temperature of 20 ℃/15℃, and the ambient temperature of 7℃/6℃.
◆The sound level is gotten from the test room, it may differ in actual use due to the ambient temperature or other causes.
◆The above parameters are of heat pump parameters.
Notes:
◆The nominal cooling cap acity is gotten in the return air temperature of 27℃/19℃, and the ambient temperature of 35℃/24℃.
◆The nominal heating capacit y is gotten in the return air temperature of 20℃/15℃, and the ambient temperature of 7℃/6℃.
◆The sound level is gotten from the test room, it may differ in actual use due to the ambient temperature or other causes.
1.6.2 High static pressure duct unit
Model Indoor unit Indoor unit MDB050T MDB060T
Nominal cooling capacity W 12500 14000
Nominal heating capacity W 14000 16500
Nominal input W 615 789
Power supply 220V～/50Hz
Air flow(High/Medium/Low) m3/h 2550/2040/1650 3000/2540/1920
ESP Pa 100 100
Dimension mm 1230×910 ×350 1430 ×910 ×350
Weight kg 69 75
Sound Level(High/Medium/Low) dB(A) 58/55/52 60/56/53
Liquid pipe outside diameterΦ mm(in) 9.52(3/8) 9.52(3/8)
pipe size Gas pipe outside diameterΦmm(in) 19.05(3/4) 19.05(3/4)
Drainage pipe inch R3/4

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Design & installation Guide For McQuay MDS Multi System
Notes:
◆The nominal cooling capacity is gotten in the return air temperature of 27℃/19℃, and the ambient temperature of 35℃/24℃
◆The nominal heating capacity is gotten in the return air temperature of 20℃/15℃, and the ambient temperature of 7℃/6℃.
◆The sound level is gotten from the test room, it may differ in actual use due to the ambient temperature or other causes.
1.6.4 Ceiling exposed/floor standing
Model Indoor unit MCM020T MCM030T MCM050T
Cooling capacity W 5800 7500 12500
Heating capacity W 5800 8000 13500
Air flow(High/Medium/Low) m3/h 1100/970/750 1300/1100/870 1850/1550/1200
Rated power input W 81 116 161
Power supply 220V～/50Hz
Dimension mm 1214x670x214 1214x670x249 1714x670x249
Weight kg 39 44 44
Sound(High/medium/Low) dB(A) 48/45/42 50/46/43 52/48/44
Liquid pipe outside diameterΦmm(in) 9.52(3/8) 9.52(3/8) 9.52(3/8)
PiPing Gas pipe outside diameterΦmm(in) 15.88(5/8) 15.88(5/8) 19.05(3/4)
Size Drain pipe mm φ20.5
Notes:
◆The nominal cooling cap acity is gotten in the return air temperature of 27℃/19℃, and the ambient temperature of 35℃/24℃.
◆The nominal heating capacity is gotten in the return air temperature of 20℃/15℃, and the ambient temperature of 7℃/6℃.
◆The sound level is gotten from the test room, it may differ in actual use due to the ambient temperature or other causes.
1.6.3 Ceiling cassette
Model Indoor unit MCK010T MCK015T MCK018T MCK020T MCK025T MCK030T MCK040T MCK050T
Nominal cooling capacity W2800 3600 4500 5400 6500 7500 10000 12500
Nominal heating capacity W 3200 3900 5000 5900 7200 8000 11000 13500
Nominal input W 26 34 36 42 75 84 110 140
Power supply 220V～/50Hz
High m3/h 520 600 650 700 1200 1300 1360 1650
Air flow Medium m3/h 430 520 550 600 1100 1060 1200 1450
Low m3/h 380 430 400 530 960 850 1110 1350
Dimension mm 930X930X278 930X930X363
Weight kg 26 30 39.5 39.5
Sound(High/medium/Low) dB(A) 29/28/26 32/30/27 38/34/30 39/35/31 42/40/38 45/43/41 46/44/42 48/45/42
Piping
Liquid pipe Φ mm(in) 6.35(1/4) 9.52(3/8) 9.52(3/8)
Size
Gas pipe Φ mm(in) 9.52(3/8) 12.7(1/2) 15.8(5/8) 19.05(3/4)
Drainage pipe mm φ20.5

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Design & installation Guide For McQuay MDS Multi System
1.6.5 Specification
Model Unit MDS030A MDS030AR MDS040A MDS040AR MDS050A MDS050AR MDS060A MDS060AR
Nominal cooling capacity kW 8.5 8.5 10 10 12.5 12.5 14.5 14.5
Nominal heating capacity kW - 9.0 - 11.5 - 13.5 - 16.5
Power supply 220V~/50Hz
Dimension Lx W x H mm
Weight kg 82 85 112 115 117 120 123 130
Cooling rated power input kW 3.0 3.0 3.5 3.6 4.4 4.4 5.0 5.0
Cooling rated current A 13.6 13.6 15.9 15.9 20 20 22.8 22.8
Heating rated power input kW - 2.5 - 3.4 - 4.2 - 4.2
Heating rated current A - 11.4 - 15.5 - 19 - 20.3
Refrigerant
R22
Type of connecting pipe copper f lare fitting & nipple joint
Liquid pipeф (mm/in)
Gas pipeф (mm/in)
Notes:
◆The nominal cooling cap acity is gotten in the return air temperature of 27℃/19℃, and the ambient temperature of 35 ℃/24℃.
◆The nominal heating capacity is gotten in the return air temperature of 20℃/15℃, and the ambient temperature of 7℃/6℃.
◆The specifications may be undated as we are trying to update the units at the time, please regard the nameplate of the unit as
standard.
840x408x900 1058x430x1044 1058x4230x1247
9.52(3/8 ″ ) 9.52(3/8 ″ ) 9.52(3/8 ″ ) 9.52(3/8 ″ )
15.88(5/8″) 19.05(3/4″) 19.05(3/4″) 19.05(3/4″)
Notes:
◆The nominal cooling cap acity is gotten in the return air temperature of 27℃/19℃, and the ambient temperature of 35℃/24℃
◆The nominal heating capacity is gotten in the return air temperature of 20℃/15℃, and the ambient temperature of 7℃/6℃.
◆The specifications may be undated as we are trying to update the units at the time, please regard the nameplate of the unit as
standard.
Connecting
accessory
pipe size
Model Unit MDS050A MDS050AR MDS060A MDS060AR
Nominal cooling capacity kW 12.5 12.5 15 15
Nominal heating capacity kW - 13.5 - 17
Power supply 380V/3N~/50Hz
Dimension L x W x H mm
Weight kg 117 120 123 130
Cooling rated power input kW 4.4 4.4 5.0 5.0
Cooling rated current A 8.4 8.4 9.6 9.6
Heating rated power input kW - 4.2 - 4.23
Heating rated current A - 8.0 - 8.8
Refrigerant R22
Liquid pipe
Gas pipe
Liquid pipeф(mm/in)
Gas pipe ф(mm/in)
1 058x430x1044 1058x430x1247
Copper flare fitting & nipple joint
Copper flare fitting & nipple joint
9.52(3/8″)
19.05(3/4″)
Connecting
accessory
pipe size
Type of
connecting
pipe

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Design & installation Guide For McQuay MDS Multi System
Notes:
◆The nominal cooling cap acity is gotten in the return air temperature of 27℃/19℃, and the ambient temperature of 35℃/24 ℃
◆The nominal heating capacity is gotten in the return air temperature of 20℃/15℃, and the ambient temperature of 7℃/6℃.
◆The sound level is gotten from the test room, it may differ in actual use due to the ambient temperature or
1.6.6 Specification
Model MDS080B MDS080BR MDS100B MDS100BR MDS120B MDS120BR MDS150B MDS150BR MDS180B MDS180BR MDS200B MDS200BR
Nominal cooling
kW 24.5 24.5 28.0 28.0 32.5 32.5 40.0 40.0 47.5 47.5 50.0 50.0
capacity
Nominal heating
kW - 26.0 - 30.0 - 34.0 - 43.0 - 50.0 - 53.0
capacity
Power supply 380V/3N～/50Hz
Sound leveldB(A) 62 62 64 64 66 66 67 67 66 66 66 66
Dimension Lx W x H mm 990x840x1840 1290x840x1840 1990x840x1840
Weight kg 275 290 285 300 290 305 355 370 520 550 560 590
Cooling rated
kW 7.5 7.5 8.5 8.5 9.8 9.8 12.9 12.9 14.1 14.1 15.2 15.2
power input
Cooling rated current A 14.6 14.6 16.8 16.8 18.8 18.8 23.1 23.1 28.2 28.2 31.1 31.1
Heating rated
kW - 7.2 - 8.3 - 9.0 - 11.1 - 13.2 - 14.7
power input
Heating rated current A - 13.6 - 15.7 - 16.7 - 22.6 - 27.1 - 29.4
Refrigerant R22
Gas side Welding & flange
Liquid side Flare fitting &nipple joint
Liquid pipeф mm(in) 12.7(1/2) 15.88(5/8)
Gas pipe ф mm(in) 28.6(11/8) 34.9(13/8)
Model MDS220B MDS220BR MDS240B MDS240BR MDS260B MDS260BR MDS280B MDS280BR MDS300B MDS300BR
Nominal coolingcapacity kW 55.0 55.0 65.0 65.0 70.0 70.0 75.0 75.0 80.0 80.0
Nominal heating capacity kW - 58.0 - 68.0 - 75.0 - 80.0 - 85.0
Power supply 380V/3N～/50Hz
Sound level dB(A) 66 66 68 68 68 68 69 69 69 69
Dimension Lx W x H mm 1990x840x1840 2280x840x1840 2580x840x1840
Weight kg 560 590 570 600 645 675 710 740 710 740
Cooling rated power input kW 16.7 16.7 19.8 19.8 21.3 21.3 22.8 22.8 26.2 26.2
Cooling rated current A 32.7 32.7 38.5 38.5 40.0 40.0 42.5 42.5 46.5 46.5
Heating rated power input kW - 16.2 - 18.5 - 20.9 - 22.0 - 23.6
Heating rated current A - 31.0 - 33.8 - 37.2 - 41.0 - 43.1
Refrigerant R22
Gas side Welding & flange
Liquid side
Flare fitting &nipple joint
Liquid pipe фmm(in) 19.05(3/4) 19.05(3/4)
Gas pipe фmm(in) 38.1(11/2) 41.3(15/8)
Connecting
accessory
pipe size
pipe
size

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Design & installation Guide For McQuay MDS Multi System
1.7 Operating Range
【Note】The t able is gotten based on the equivalent length of 16m and the height is 0 m.
1.8 Refnet
1.8.1“Y”type
unit：mm
Length(mm) Diameter(mm) Diameter(mm) Diameter(mm)
Refnet A B C D
E(outer
F G H
I(outer
J K L M
N(outer
O P Q R
model
diamenter diamenter diamenter
MDS-Y1 553 172 293 120 28.6 28.9 25.7 22.5 28.6 28.9 25.7 22.5 19.3 22.2 19.3 16.1 12.9 9.7
MDS-Y2 420 142 223 80 15.88 16.1 12.9 9.7 12.7 12.9 9.7 6.5 12.7 12.9 9.7 6.5
MDS-Y3 420 142 223 80 15.88 16.1 12.9 9.7 12.7 12.9 9.7 6.5 15.88 16.1 12.9 9.7
MDS-Y4 493 142 223 80 22.2 22.5 19.3 16.1 19.1 19.3 16.1 12.9 9.7 19.1 19.3 16.1 12.9

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Design & installation Guide For McQuay MDS Multi System
1.8.2 Distributor kit
unit: mm
Type: MDS-C1
Type: MDS-Y5
unit: mm