Midea V4 Plus S Series Operating manual

3 phase, 380-415V, 50Hz
MDVS-252(8)W/DRN1
MDVS-280(10)W/DRN1
MDVS-335(12)W/DRN1
Model:
Technical Service Manual
V4 Plus
Water Cooled VRF

001 Part 1 General Information
010 Part 2 Selection Procedure
015 Part 3 Specifications & Performances
170 Part 4 Installation
198 Part 5 Troubleshooting
Contents

MCAC-VTSM-2016-04 R410A DC Inverter VRF V4 Plus W Series 50Hz
General Information 1
Part 1 General Information
1. V4+W VRF system introduction.............................................................2
2. Features ...................................................................................................2
3. Main units lineup.....................................................................................6
4. Indoor units lineup..................................................................................6
5. Nomenclature ..........................................................................................9

R410A DC Inverter VRF V4 Plus W Series 50Hz MCAC-VTSM-2016-04
2 General Information
1. V4+W VRF system introduction
Midea water source heat pump central air-conditioning system is a kind of VRF air-conditioning system which
uses water as the cold/heat source. In this system, water is transported from the cold/heat source to the main
unit through the water pipe, after the heat exchange between water and the refrigerant, main unit will send the
refrigerant to indoor units.
2. Features
2.1 Wide application range
2.1.1 Free combination, maximum capacity can be up to 36HP
The capacity range of main units is from 8HP to 36HP. Maximum 59 indoor units with capacity up to 130% of
total main units can be connected in one system.
2.1.2 Wide operation range
Main unit water inlet flow: 8HP (2.7~8.1m3/h); 10HP (3~9 m3/h); 12HP (3.6~10.8 m3/h).
2.1.3 Long piping length
Piping length
Permitted
value (m)
Actual total piping length
300
Longest piping
Actual length
120
Equivalent length
150
Equivalent piping length from the farthest indoor
unit to the first indoor branch joint
40/90*
Level difference between
indoor and outdoor units
Main unit up
50
Main unit down
40
Level difference between indoor units
30
Main unit ambient temperature: 0~40oC
Main unit water inlet temperature: 7~45oC
Indoor temperature in cooling mode: 17~32oC
Indoor temperature in heating mode: 15~30oC
*The allowable length extend to 90m should under certain conditions.
Please refer to the installation manual for details.

MCAC-VTSM-2016-04 R410A DC Inverter VRF V4 Plus W Series 50Hz
General Information 3
2.2 High efficiency
2.2.1 High efficiency DC inverter compressor
All series of 8HP, 10HP and 12HP adopt one DC inverter compressor each. With DC inverter compressors, V4
Plus W Series offers increases energy efficiency by 25%.
2.2.2 High efficiency double-pipe heat exchanger
With the innovative designed double-pipe heat exchange technology, the water quality required is low. The
water side has large circulation area, and it is not easy to get stuck, higher reliability, easy to clean and
maintenance.
2.2.3 Wide side heat recovery
In the modern large-scale buildings, the load between the internal and external areas is different. It may occur
situations that both cooling and heating are required. The V4 PLUS W series modular design, not only can
realize meticulous system division in different areas but also can realize heat recovery at the same time,
significantly improved energy efficiency.
New structure enhanced mid-frequency performance
Special designed scroll profile for R410A
More compact, weight reduced by 50%
Advanced permanent magnet DC motor improves
low-frequency band performance

R410A DC Inverter VRF V4 Plus W Series 50Hz MCAC-VTSM-2016-04
4 General Information
2.3 High reliability
2.3.1 Cycle duty operation
V4+W intelligent control, according to the system load, cyclically changes start-up sequence of multiple main
units, equalizes compressor duty and extends operation life-span.
Note: Everytime after oil-returning/defrosting or restart, main unit will start in different sequence.
2.3.2 Backup operation
In a multiple system, if one module is failed, other modules can be backup instead of the failed one for
continuing operation.
2.3.3 No effect of climate on the operation
Due to the stable source of water as the cold/heat source of the system, both in cold winter and hot summer,
air conditioning capacity won't be influenced by the environmental temperature. Especially when heating in
winter, the unit does not exist frost/defrost process, making the heating effect more stable and strong.
2.3.4 No water leakage
No water piping is installed in the indoor area for eliminating leakage risks.

MCAC-VTSM-2016-04 R410A DC Inverter VRF V4 Plus W Series 50Hz
General Information 5
2.4 Enhanced comfort
2.4.1 Low noise
Without outdoor units fan noise and fully enclosed design which realize lower noise.
2.5 Easy installation and service
2.5.1 Compact and lightweight
8,10,12HP three basic model with the same size and weight: W780mm×H1000mm×D550mm, 146kg.
It can be transported through the elevator or forklift.
More compact, can also be installed in the narrow space of the engine room.
2.5.2 Modular design
Modular design, one main unit can be installed above another one and greatly saved installation space.
Various installation environment: Storehouse, basement, close balcony, corridor, plant room and so on.
2.5.3 Auto addressing
Outdoor unit can distribute address for each indoor unit automatically.
Wireless and wired controllers can enquire and modify each indoor unit’s address.
2.5.4 Simple signal line connection
Installation is easier as communication wiring can be shared by indoor & outdoor units. It’s easy for the user to
retrofit the existing system with a centralized control by simply connecting to the outdoor units.
PQE & XYE: only one set of PQE communication wires can achieve communication among indoor units,
outdoor units and the network.
Reversible communication, central controller can be connected from indoor side or outdoor side as you
wish.

R410A DC Inverter VRF V4 Plus W Series 50Hz MCAC-VTSM-2016-04
6 General Information
3. Main units lineup
8, 10, 12 HP
16 ,18 ,20, 22, 24 HP
26, 28, 30, 32, 34, 36 HP
Main unit combinations
Capacity
Model
Recommend combination
Max. indoor
units nos.
(HP)
8(HP)
10(HP)
12(HP)
8
MDVS-252(8)W/DRN1

13
10
MDVS-280(10)W/DRN1

16
12
MDVS-335(12)W/DRN1

19
16
MDVS-504(16)W/DRN1

23
18
MDVS-532(18)W/DRN1


29
20
MDVS-560(20)W/DRN1

33
22
MDVS-615(22)W/DRN1


36
24
MDVS-670(24)W/DRN1


39
26
MDVS-784(26)W/DRN1


43
28
MDVS-812(28)W/DRN1


46
30
MDVS-840(30)W/DRN1

50
32
MDVS-895(32)W/DRN1


53
34
MDVS-950(34)W/DRN1


56
36
MDVS-1005(36)W/DRN1


59
4. Indoor units lineup
Capacity
Cassette unit

MCAC-VTSM-2016-04 R410A DC Inverter VRF V4 Plus W Series 50Hz
General Information 7
(×100W)
One-way cassette
Two-way cassette
Compact four-way
cassette
Four-way cassette &
Four-way cassette
silent type
18
22
28
36
45
56
71
80
90
100
112
140
Capacity
(×100W)
Duct unit
Low static
pressure duct
A5 duct
High static pressure duct
18
22
28
36
45
56
71
80
90
112
140
160
200
250
280
400
450
560
Indoor units lineup
Capacity
Floor-standing/Ceiling & Floor/Console

R410A DC Inverter VRF V4 Plus W Series 50Hz MCAC-VTSM-2016-04
8 General Information
(×100W)
Cased floor-standing
Uncased floor-standing
Ceiling & floor
console
22
28
36
45
56
71
80
90
112
140
160
Capacity
(×100W)
Wall mounted/Fresh air processing unit
Wall mounted
(S panel)
Wall mounted
(M panel)
Wall mounted
(R panel)
Fresh air processing unit
22
28
36
45
56
71
80
90
125
140
200
250
280
Note:
Due to continuous improvement, specifications are subject to change without prior notice.

MCAC-VTSM-2016-04 R410A DC Inverter VRF V4 Plus W Series 50Hz
General Information 9
5. Nomenclature
5.1 Main unit
MDV S –252 (8) W / D R N1
5.2 Indoor unit
MDV –D 28 Z / D D V N1 A
Meaning of the code*
Type code
Meanings
Type code
Meanings
Q1
One way cassette
T3
Low static pressure duct
Q2
Two way cassette
G
Wall mounted
Q4
Four way cassette
DL
Ceiling & floor
Q4-A
Four way cassette (compact)
Z-F
Floor standing (F4/F5: Exposed ; F3: Concealed)
T1
High static pressure duct
Z
Console
T2
Medium static Pressure duct
T1-FA
Fresh air processing unit
Refrigerant type
N1:R410A Omit for R22
Power Supply
R: 380~415V, 50Hz, 3N
Inverter Type
D:DC Inverter Omit for AC Inverter
Main unit
Rated Capacity (HP), (only for combinable type)
Cooling Capacity (×100W)
Water source type
Midea VRF
Series code
Refrigerant type N1: R410A
Power supply type
V: 220-240V~60Hz
Omit: 220-240V~50Hz
Electrical Auxiliary Heater
D: with EAH
Omit: without EAH
Motor Type
D: DC Fan Motor
Omit: AC fan Motor
Indoor unit type* (refer to below table)
Cooling Capacity (×100W)
VRF Indoor Unit
Midea

R410A DC Inverter VRF V4 Plus W Series 50Hz MCAC-VTSM-2016-04
10 Selection Procedure
Part 2 Selection Procedure
1. Introduction ...........................................................................................11
2. Unit Selection (Based on cooling load)...............................................14

MCAC-VTSM-2016-04 R410A DC Inverter VRF V4 Plus W Series 50Hz
Selection Procedure 11
1. Introduction
1.1 Model selection procedure
Select the model and calculate the capacity for each refrigerant system according to the procedure shown
below.
Calculate the indoor air-conditioning load, calculate the maximum air-conditioning load for each room or
zone.
Selection of an air conditioning system
Select the ideal air conditioning system for air conditioning of each room or zone.
Design of the control system
Design a suitable control system for the selected air conditioning system.
Preliminary selection of indoor and outdoor units
Make preliminary selections that are within the allowable range for the system.
Check the tubing length and elevation difference
Check that the length of refrigerant tubing and the elevation difference are within the allowable ranges.
Calculation of the corrected outdoor unit capacity
Capacity correction coefficient for model, outdoor temperature conditions, tubing length and elevation
difference.
Calculation of the actual capacity for each indoor unit
Calculate the corrected indoor/outdoor capacity ratio, based on the corrected outdoor unit capacity and
the total corrected capacity of all indoor units in the same system.
Recheck the actual capacity for each indoor unit
If the capacity is inadequate, reexamine the unit combinations.
1.2 Indoor unit selection
Enter INDOOR UNIT CAPACITY TABLES at given indoor and outdoor temperature. Select the unit that the
capacity is the nearest to and greater than given load.
Note:
Individual indoor unit capacity is subject to change by the combination. Actual capacity has to be calculated
according to the combination by using outdoor unit capacity table.
1.2.1 Calculation of Actual Capacity of Indoor Unit
Because the capacity of a multi air-conditioner changes according to the temperature conditions, tubing length,
elevation difference and other factors, select the correct model after taking into account the various correction
values. When selecting the model, calculate the corrected capacities of the outdoor unit and each indoor unit.
Use the corrected outdoor unit capacity and the total corrected capacity of all the indoor units to calculate the
actual final capacity of each indoor unit.
Find the indoor unit capacity correction coefficient for the following items
Capacity correction for the indoor unit temperature conditions
From the graph of capacity characteristics, use the indoor temperature to find the capacity correction
coefficient.
Capacity distribution ratio based on the indoor unit tubing length and elevation difference.
First, in the same way as for the outdoor unit, use the tubing length and elevation difference for each
indoor unit to find the correction coefficient from the graph of capacity change characteristics
Capacity distribution ratio for each indoor unit = Correction coefficient for that indoor unit / Correction
coefficient for the outdoor unit

R410A DC Inverter VRF V4 Plus W Series 50Hz MCAC-VTSM-2016-04
12 Selection Procedure
1.3 Outdoor unit selection
Allowable combinations are indicated in INDOOR UNIT COMBINATION TOTAL CAPACITY INDEX TABLE.
In general, outdoor unit can be selected as follows though the location of the unit, zoning and usage of the
rooms may be considered.
The indoor and outdoor unit combination is determined that the sum of indoor unit capacity index is nearest to
and smaller than the capacity index at 100% combination ratio of each outdoor unit. Up to 13~20 indoor units
can be connected to one outdoor unit. It is recommended to choose a larger outdoor unit if the installation
space is large enough.
If the combination ratio is greater than 100%, the indoor unit selection shall be reviewed by using actual
capacity of each indoor unit.
INDOOR UNIT COMBINATION TOTAL CAPACITY INDEX TABLE
Outdoor Unit
Indoor Unit Combination Ratio (kW)
130%
120%
110%
100%
90%
80%
70%
60%
50%
8HP
32.8
30.2
27.7
25.2
22.7
20.1
17.6
15.1
12.6
10HP
36.4
33.6
30.8
28.0
25.2
22.4
19.6
16.8
14.0
12HP
43.6
40.2
36.9
33.5
30.2
26.8
23.5
20.2
16.8
16HP
65.52
60.48
55.44
50.4
45.36
40.32
35.28
30.24
25.2
18HP
69.2
63.8
58.5
53.2
47.9
42.6
37.2
31.9
26.6
20HP
72.8
67.2
61.6
56.0
50.4
44.8
39.2
33.6
28.0
22HP
80.0
73.8
67.7
61.5
55.4
49.2
43.1
36.9
30.8
24HP
87.1
80.4
73.7
67.0
60.3
53.6
46.9
40.2
33.5
26HP
101.92
94.08
86.24
78.4
70.56
62.72
54.88
47.04
39.2
28HP
105.56
97.44
89.32
81.2
73.08
64.96
56.84
48.72
40.6
30HP
109.2
100.8
92.4
84.0
75.6
67.2
58.8
50.4
42
32HP
116.35
107.4
98.45
89.5
80.55
71.6
62.65
53.7
44.75
34HP
123.5
114
104.5
95
85.5
76
66.5
57
47.5
36HP
130.65
120.6
110.55
100.5
90.45
80.4
70.35
60.3
50.25
INDOOR UNIT CAPACITY INDEX
Unit Size
Model
22
Model
28
Model
36
Model
45
Model
56
Model
71
Model
80
Model
90
Model
112
Model
140
Capacity Index (kW)
2.2
2.8
3.6
4.5
5.6
7.1
8.0
9.0
11.2
14.0
Unit Size
Model
160
Model
200
Model
250
Model
280
Capacity Index (kW)
16
20
25
28
1.4 Actual performance date
Use OUTDOOR UNIT CAPACITY TABLES.
Determine correct table according to the outdoor unit model and combination ratio.
Enter the table at given indoor and outdoor temperature and find the outdoor unit capacity and power input.
The individual indoor unit capacity (power input) can by calculated as follows.
IUC=OUC ×INX/TNX
Where,
IUC: Each indoor unit capacity
OUC: Outdoors unit capacity
INX: Each indoor unit capacity index
TNX: Total capacity index
Then, correct the indoor unit capacity according to the piping length.
If the corrected capacity is smaller than the load, the size of indoor unit has to be increased and repeat the
same selection procedure.

MCAC-VTSM-2016-04 R410A DC Inverter VRF V4 Plus W Series 50Hz
Selection Procedure 13
1.5 Variation in capacity in accordance with the length of refrigerant pipe
1.5.1 Cooling capacity modification
Modification coefficient of the length and high difference of refrigerant pipe:
L: Refrigerant pipe equivalent length
H: Height difference between outdoor and indoor unit. Positive data means outdoor unit is top. Negative data
means outdoor unit is down.
1.5.2 Heating capacity modification
Modification coefficient of the length and high difference of refrigerant pipe:
L: Refrigerant pipe equivalent length
H: Height difference between outdoor and indoor unit. Positive data means outdoor unit is top. Negative data
means outdoor unit is down.

R410A DC Inverter VRF V4 Plus W Series 50Hz MCAC-VTSM-2016-04
14 Selection Procedure
2. Unit Selection (Based on cooling load)
2.1 Given condition
Design condition (Cooling: Indoor 20°C (WB), Outdoor 35°C (DB))
Cooling load:
Location
Room A
Room B
Room C
Room D
Room E
Room F
Load (kW)
2.1
2.8
3.5
4.6
5.8
7.2
Power supply unit: Outdoor 380~415V-3Ph-50Hz, Indoor 220~240V-1Ph-50Hz.
Pipe length: 50m
Height difference: 30m
2.2 Indoor unit selection
Select the suitable capacity for condition of ‘Indoor 20°C (WB), Outdoor 35°C (DB)’ using indoor unit capacity
table. The selected result is as follows. (Assuming the indoor unit type is duct)
Location
Room A
Room B
Room C
Room D
Room E
Room F
Load (kW)
2.1
2.8
3.5
4.6
5.8
7.2
Unit size
22
28
36
45
56
71
Capacity (kW)
2.3
2.9
3.7
4.8
6.0
7.5
2.3 Outdoor unit selection
a) Assume the indoor unit and outdoor unit combination as follows
Calculate the total nominal capacity of indoor units in the combination according to the above table:
2.2×1+2.8×1+3.6×1+4.5×1+5.6×1+7.1×1=25.8kW
Select outdoor unit: MDVS-280(10)W/DRN1 which has nominal cooling capacity: 28kW.
Calculate the proportion between ①and ②: 258/280= 92%
b) Result : Because the proportion is within 50～130%, it is a Right selection.
c) Real function data with indoor unit combination
For the 92% combination, calculate the cooling capacity of outdoor unit (MDV-280(10)W/DRN1(B)).
26.65KW ←90% (Indoor temperature : WB 20°C, Outdoor temperature: DB 35°C)
29.61KW ←100%(Indoor temperature : WB 20°C, Outdoor temperature: DB 35°C)
Then calculated the outdoor capacity in 92% combination index:
Therefore: 26.65+ {(29.61-26.65)/ 10} ×2= 27.24;
Outdoor unit (MDVS-280(10)W/DRN1 cooling temperature: DB 35°C
Capacity modification coefficient with pipe length (50m) and height difference (30m): 0.958
Each indoor unit cooling capacity:
MDV-D22T2: 27.24 ×22/258 ×0.958 = 2.22(kW)
MDV-D28T2: 27.24 ×28/258 ×0.958 = 2.83 (kW)
MDV-D36T2: 27.24 ×36/258 ×0.958 = 3.64 (kW)
MDV-D45T2: 27.24 ×45/258 ×0.958 = 4.55 (kW)
MDV-D56T2: 27.24 ×56/258 ×0.958 = 5.66 (kW)
MDV-D71T2: 27.24 ×71/258 ×0.958 = 7.18 (kW)
Location
Room A
Room B
Room C
Room D
Room E
Room F
Load (kW)
2.1
2.8
3.5
4.6
5.8
7.2
Unit size
22
28
36
45
56
71
Capacity (kW)
2.22
2.83
3.64
4.55
5.66
7.18
2.4 Conclusion
Generally, we think this result is acceptable, so we can think we have accomplished the calculation. But if you
think this result is not acceptable, you can repeat the above process.
Remark: In this sample, we don’t consider the other capacity modification index and assume them are 1.0.
For more details about the effect factor such as outside ambient/inside ambient DB/WD, please refer to the
performance table of indoor and outdoor units.

MCAC-VTSM-2016-04 R410A DC Inverter VRF V4 Plus W Series 50Hz
Specification & Performance 15
Part 3 Specification & Performance
1. Specifications........................................................................................16
2. Dimensions............................................................................................18
3. Piping diagrams ....................................................................................18
4. Electric Characteristics ........................................................................20
5. Electric wiring........................................................................................21
6. Capacity Tables .....................................................................................28
7. Accessories.........................................................................................168
8. Functional parts and safety devices..................................................169

R410A DC Inverter VRF V4 Plus W Series 50Hz MCAC-VTSM-2016-04
16 Specification & Performance
1. Specifications
Model
MDVS-252(8)W/
DRN1
MDVS-280(10)W/
DRN1
MDVS-335(12)W
/DRN1
Power supply
V-Ph-Hz
380~415V 3Ph ~ 50Hz
Cooling (*1)
Capacity
W
25200
28000
33500
Input
W
4800
6100
8000
EER
W/W
5.25
4.59
4.19
Heating (*2)
Capacity
W
27000
31500
37500
Input
W
4450
5830
7800
COP
W/W
6.07
5.40
4.81
IPLV©
5.9
5.8
5.8
Max. input consumption
W
9454
9454
11188
Max. current
A
23
23
23
DC Inverter
compressor
Model
E655DHD-65D2YG
Quantities
1
Type
DC Inverter
Brand
Hitachi
Capacity
W
31590
Input
W
10340
Power supply
V-Ph-Hz
380-415V~3Ph, 50Hz
Operating
frequency
Hz
40~200
Crankcase
W
40～80
Refrigerant oil
ml
FVC68D / 500
Heat exchanger
Type
Double-pipe heat exchanger
Rated water flow
volume
m3/h
5.4
6
7.2
Pressure drop
kPa
35
40
48
Max pressure
of water pipe side
MPa
1.98
Drainage pipe outside diameter
mm
Ф10
Water side connecting pipe
mm
DN32 inner groove
Outdoor sound level(*3)
dB(A)
51
52
52
Main unit
Dimension
(W×H×D)
mm
780×1000×550
Packing
(W×H×D)
mm
845×1170×600
Net/Gross weight
kg
146/155
147/156
Charged refrigerant type and volume
kg
R410A 2kg
Throttle type
EXV
Excessive operating pressure
MPa
4.4/2.6
Refrigerant piping
Liquid side/ Gas
side(*4)
mm
Ф12.7/Ф25.4
Ф12.7/Ф25.4
Ф15.9/Ф31.8
Oil balance pipe
mm
Ф6.35

MCAC-VTSM-2016-04 R410A DC Inverter VRF V4 Plus W Series 50Hz
Specification & Performance 17
Total pipe length
m
300
The farthest pipe
length(actual)
m
120
The farthest pipe
length (equivalent)
m
150
The farthest
equivalent pipe
length from the first
distributor (*5)
m
40(90)
Max. Vertical pipe
length (When main
units is above)
m
50
Max. Vertical pipe
length (When main
units is below)
m
40
Max. drop between
indoor units
m
30
Connection wiring
Power wiring
mm2
4×10+10(L≤20m);
4×16+10(L≤50m)
Signal wiring
mm2
3 core shielded wiring;
wiring dia.≥0.75
Main unit water inlet temp.
℃
7℃－45℃
Main unit ambient temp. range
℃
0℃－40℃
Main unit ambient humidity
Below 80%
Notes:
1. The cooling conditions: indoor temp.: 27℃DB, 19℃WB, outdoor temp.: 35℃DB, water inlet temp. :30℃, equivalent pipe length:
5m, drop length: 0m.
2. The heating conditions: indoor temp.: 20℃DB, 15℃WB, outdoor temp.: 7℃DB, 6℃WB, water inlet temp. :20℃, equivalent
pipe length: 5m drop length: 0m.
3. Sound level: Anechoic chamber conversion value, measured at a point 1 m in front of the unit at a height of 1 m. During actual
operation, these values are normally somewhat higher as a result of ambient conditions.
4. Connection piping diameter of single-unit is the stop valve diameter of the unit.
Connection piping diameter of multi-unit is the main pipe connecting to the first indoor branch joint, is case of the total equivalent
liquid length is less than 90m. If the total equivalent liquid length is more than 90m, please refer to technical manual to choose the
connection piping diameter.
5. The farthest equivalent pipe length should be equal to or shorter than 40m, but it can be up to 90m if meet the required
conditions following part 4 installation sections.
The above data may be changed without notice for future improvement on quality and performance.

R410A DC Inverter VRF V4 Plus W Series 50Hz MCAC-VTSM-2016-04
18 Specification & Performance
2. Dimensions
8HP/10HP/12HP (unit: mm)
3. Piping diagrams
Inverter
compressor
Oil separator
ST
EXVB
SV2
SV4
Electronic expansion valve
Electromagnetic valve
Filter
Pressure sensor
Pressure Switch
Way valve
Symbol Description
Temperature probe SV3
Pressure relief valve
TSC1
TSC2
TSJ
T7
EXVA