Midea MDV-D280W/SN2, MDV-D280W/S, MDV-D560W/SN2, MDV-D560W/S, MDV-D840W/SN2 Installation Manual

Liquid Side Piping
Diameter

Refrigerant to be Added
per meter piping

H 15m

L

1

L

2

L

3

L

4

L

5

L

6

A

B

C

D

E

F

G

H

I

Outdoor Unit (one or more outdoor units)

The first Line Branch Pipe

Indoor Unit

Indoor Unit

Indoor Unit to Indoor Unit

Drop Height

Maximum Piping Equivalent Length L 125m

(From the first Line branch pipe) Maximum piping
Equivalent Length L 40m

Header Branch Pipe

Drop Height between Indoor

unit and outdoor Unit H 50m

Branch Piping between indoor units
(Indoor piping)

Refer to table 3 for indoor unit connection
pipes.

Branch Connection Selection
Select according to the indoor units general
design capacity which it connects to.But if
the indoor units design capacity is more than
the outdoor unit design capacity, then select
branch connection according to the outdoor
unit.
Header Branch Selection.
The selection should according to the
number of branches it connects to.

3

Branch Piping between branches
Select pipe diameters according to the
table 2.

2

MDV-D280W/S
MDV-D560W/S
MDV-D840W/S

Digital Scroll Central Air Conditioner
(Outdoor Unit)

Installation Manual

PRECAUTION

Precautions before reading the installation
manual.

1. This installation manual is for the outdoor
unit.

2. Refer to the indoor unit installation manual
for indoor parts installation.

3.Please read the power source unit installation
manual to install the power source unit .

4. Please refer to the refrigerant distributor
installation manual to install the refrigerant
distributor.

IMPORTANT CHECKING POINTS DURING INSTALLATION

INSTALLATION

Confirm the model and name of your air
conditioner to avoid installation mistakes.

REFRIGERANT PIPING

Separately purchased refrigerant distribu­tor (branch connection, header branch
pipe) should be used in the process or
refrigerant piping.
Refrigerant piping should meet the specifi­ed diameters.
Charge nitrogen under certain pressure in
the refrigerant piping before welding.
Refrigerant piping should undergo the heat
insulation process.
After the installing refrigerant piping, do not
electrify the indoor unit before the airtight
test and vacuum.

AIRTIGHT TEST

Refrigerant piping must be tested for gas

2

proof [2.94Mpa(30kg/cm ) nitrogen]

VACUUM

Vacuum pump must be used, and vacuum­ing should be done from the gas side and
liquid side simultaneously.

ADD REFRIGERANT

When the actual pipe length is longer than
the base length,the every outdoor unit added
refrigerant volume is decided on the
calculating according to the actual length
of pipes.
Fill the form on the outdoor unit electric
control box with the added volume, length
of pipes (actual length) and the relative
height drop between outdoor unit and indoor
unit.

WIRING

Choose power capacity and wire diameter
according to the design manual.The power
cord of the air conditioner should be wider
than the power cord of ordinary motor.
Never enwind or cross the power cord
(380V~) with signal wire (low voltage)
between indoor and outdoor unit, or malfunction is unavoidable.
Connect the indoor unit to the power after airtight test and vacuuming.

INSTALLATION LOCATION

CAUTION:

There is combustible gas leakage existing.
There is much oil (including engine oil)
ingredient.

1. Please keep away from the following
place, or malfunction of the machine
may be caused:

There is salty air surrounding(near the
coast)
There is caustic gas (the sulfide, for exa­mple) existing in the air (near a hotspring).
A place the heat air expelled out from the
outdoor unit can reach your neighbor's
window.
A place that the noise interferes your
neighbors every day life.
A place that is too weak to bear the
weight of the unit.
Uneven place.
Insufficient ventilation place.
Near a private power station or high
frequency equipment.

2. The insulation of the metal parts of the
building and the air conditioner should
comply with the regulation of National
Electric Standard.

1. Enough repairing space showing below
should be left during installation. When
install the outdoor unit, set the power
equipment at the side of the outdoor
unit, please refer to the power equipm­ ent installation manual.

2. Be sure to left enough room for installat­ ion and maintenance. (See Fig. Below)

INSTALLATION SPACE

Air-out

Air-in

Air-in

Install & Repair Surface.

10mm

10mm

1000mm

Or more

Or more

10mm

(Facade)

10mm or more

1000mm or more

Outdoor unit platform

NOTE: 1. Let the obstacle above the outdoor
unit at least 2000mm away.

2. The top of any pile around the outdoor
unit should at least 400mm below the unit top.

REFRIGERANT PIPING

1. Please remove the left-hand board first for
the connection of the refrigerant piping is ins­ ide the outdoor unit.(M6: 4; M4:1)

2. The pipe can be lead out through the down­ left corner of the front of the outdoor unit or
the soleplate gap.

3. When through out of the front, lead the pipe
out by wiring from the panel,and install the
refrigerant distributor at left or at right.

4. After through out of the soleplate, install
the refrigerant distributor at left,right or
rear direction.

5. When through out from the front, seal the so­ leplate gap with the rubber board to keep the
dust and rubbish out of the unit.

(M6)

(M4)

Soleplate for
piping and
wiring

Soleplate

Rear-Leading

piping

Left-Leading

piping

Left-Leading

piping

Right-Leading

piping

Panel for serving

Right-Leadin

g

piping

Select Sizes of Refrigerant Pipes and Materials

Select Sizes of Refrigerant Pipes

Outdoor Unit the Piping at the first
branch (Main piping)

Refer to table 1 for outdoor unit pipe
sizes.

1

1

1.25

1.7

2

2.5

3

3.2

4

5

Outdoor Unit

Capacity Rating

28 type

80type

36 type

90 type

45 type

56 type

112 type

140 type

71 type

Capacity Rating

Capacity

(horsepower)

Capacity

(horsepower)

Capacity of outdoor

unit(horsepower)

Sum Capacity of indoor

unit(horsepower)

Maximum Quantity

of Indoor unit

Size and Connecting Method

f28.6(Welding)

f38.0(Welding)

f45.0(Welding)

f12.7(Flaring nut)

f19.0(Flaring nut)

f22.0(Welding)

1. Table 1
Piping sizes and connecting method of the
outdoor unit.

MDV-D280W/SN2
MDV-D280W/S

MDV-D560W/SN2
MDV-D560W/S

MDV-D840W/SN2
MDV-D840W/S

Models

Gas Side

Liquid Side

2. Table 2
Piping sizes at the branch pipe
A: the total HP of indoor units

Header branch pipe

Branch joint

Note: The indoor unit must be connected with
MDV-HY1041 directly ,the further branch
connection is not allowed.

Length and Drop Height Permitted of the Refrigerant piping

100m

125m

40m

50m

30m

15m

250m

300m

L1+L2+L3+L4+L5+L6+L7

L1+L3+L4+L5+L6+j

L3+L4+L5+L6+j

+A+b+c+d+e+f+g+h+i+j

Permitted value

Total Pipe Length (Actual)

Maximum Piping (L)

Indoor Unit to Indoor Unit Drop Height

Indoor Unit-Outdoor
Unit Drop Height

Piping (farthest from the first line
pipe branch) Equivalent Length

Actual Length
Equivalent Length

Outdoor Unit Up
Outdoor Unit Down

Pipe Length

Drop

Height

Piping

Make sure there is no any dirt or water
before connecting the piping to the outdoor
Units.
Wash the piping with high pressure nitrogen,
never use refrigerant of the outdoor unit.

Remove Dirt or Water in the Piping

Airtight Test

Charge pressured nitrogen after connecting
indoor unit/outdoor unit piping to do airtight
test.

2

1. Pressured nitrogen [2.94MPa (30kg/cm )]
should be used in the airtight test.

2. Tighten high pressure/low pressure
valves before applying pressured nitrogen.

3. Apply pressure from air vent mouth on the
high pressure/low pressure valves.

4. The high pressure/low pressure valves
are closed when applying pressured nitrogen.

5. The airtight test should never use any
oxygen, flammable gas or poisonous gas.

Air Purge with Vacuum Pump

Open All Valves

Refrigerant Amount to be Added

Using vacuum pump to do the vacuum,never
using refrigerant to expel the air .
Vacuuming should be done from both liquid
side and gas side simultaneously.

Calculate the added refrigerant according to the
diameter and the length of the liquid side
pipe of the outdoor unit/indoor unit connection.

TEST RUNNING

The test running can not begin until the outdoor unit has been connected to the power for 12hr.

1. Sling the outdoor unit and carry it in with
4 steel wire (f6mm or more)

2. Use soft board to protect the unit surface
from scratch and distortion at where contact
the steel wire.

CARRY IN THE OUTDOOR UNIT

20

Steel wire

Mopboard

Soleplate

Give owner

Give owner

For maintenance

For the toggle switch

MDV-D280W/S(N2)
MDV-D560W/S(N2)

MDV-D840W/S(N2)

1

1

2

1

1

ACCESSORIES(outdoor unit)

Model

Name

Outline

Usage

Outdoor unit installation manual

Screws bag

Screw driver

This manual

Outdoor unit owner s manual
Indoor unit owner s manual

Model: MDV-D280W/SN2

MDV-D560W/SN2

MDV-D840W/SN2

MDV-D280W/S(N2)

MDV-D560W/S(N2)

MDV-D840W/S(N2)

10

20

30

16

20

30

5~13.5

10~27

15~40.5

2. Table 1
Select branch pipe

NAME

PIPE LOCATION

NUMBER IN THE TABLE

Directly connect to the
indoor unit

No directly connect to
the indoor unit

3

1, 2

A(HP)

Header branch pipe
(Gas side/ liquid side)

Branch joint

A< 10
10< A < 20
20<A < 30

f 28.6/ f 12.7
f 38.0 / f 19.0
f 45.0 / f 22.0

4. Table 4
Piping sizes and connecting method of the
Indoor Unit.

f19.0(Flaring nut) f9.5(Flaring nut)

Gas Side

Liquid Side

10 HP

20 HP & 30 HP

f 9.5

f 12.7

f 15.9

f 19.0

f 22.0

0.065kg

0.115kg

0.190kg

0.290kg

0.380kg

Low
Pressured
Valve

High
Pressured
Valve

Joint

Indoor Unit
& Branch pipe

Terminal
Connecting
Block

Connecting
signal wire

Connecting
power wire

Connecting
power wire

MDV03I-017bW

MDV-BY101 MDV-HY1041

MDV-BY102

MDV-BY103

11

223322 22 22 22 22

33 33 33 33 33 33 33

11

33

33

33

33

11

22

22

22 22

33 33 33 33

33

33 33

33

Outdoor Unit

Outdoor Unit

Outdoor Unit

CAUTION

To prevent the refrigerant piping from oxidiz­ing inside when welding, it is necessary to
charge nitrogen, or oxide will choke the
circulation system.

CAUTION:

Name Quantity

2-core

Size

Indoor/Outdoor Unit Signal Wire

22

1.0mm 500m RVVP-1.0mm X2

Model of indoor unit

Room Name
For example: Indoor unit (A)
of the first system on second
floor is record as: 2F 1A.

Outdoor Unit

Ground

(Open)

(Series Control)

(Open)

Indoor/Outdoor
Unit Signal
Wire

Close end of the connection shield wire

ITEM

MODEL

Non Electric
Heating

Electric
Heating

Indoor Unit

Power
source

2

Minimum wire diameter(mm )
Dimension(m)
(continuous length)

2.0

(30m)

3.5

(50m)

f1.6mm

30

15

Single
Phase
220V~
50Hz

3-Phase
380V~
50Hz

Leakage
protector

Grounding Capacity

Fuse

Manual switch(A)

20A 30mA

0.1sec or
less

£¬

Distance between foot screws is shown as follow.

(15x20 Long hole)

A

B

C

Air inlet snow proof shed Air outlet snow proof shed

Air inlet snow proof shed

2. In snowy places, equipment should be installed to prevent
snow.(As the figure below)(defective snow proof equipment
is easy to cause malfunction).To reduce the affection by
collective snow, please lift the bracket high, and install shelf
at the air inlet and air outlet.

ELECTRICAL WIRING

CAUTION:

Please select power source for indoor unit and outdoor unit

respectively.

The power supply has specified branch circuit with leakage
protector and manual switch.
The power supply leakage protector and manual switch
on all the indoor unit connecting to the same outdoor unit
should be universal.(Please set all the indoor unit power
of one system into the same branch circuit.)
Please put the connective piping system between indoor
unit and outdoor unit with the refrigerant system together.
Use 2-core screened wire as indoor and outdoor control
wire.
Please design a separate circuit for compressor heater
inside the unit for it is frequently heated in using season.
The installation should comply with relevant national electric
standard.
Power wiring should be engaged by specialized electrician.

< Outdoor Unit Wiring>

Separate Power Supply (without power facility)(Table 1)

ITEM

MODEL

Power
source

2

Minimum wire diameter(mm )
Dimension(m)
(continuous length)

MDV-D280W/SN2
MDV-D280W/S

25(46)

16(29)

35(78)

16

60 50

380~415V

3N~
50Hz

Leakage
protector

Grounding Capacity

Fuse

Manual switch(A)

100mA

0.1sec or
less

POWER WIRING

NOTE: The wire diameter and continuous length is under the

condition that the voltage vibration is within 2%. If the
continuous length is exceed the above value, choose
the wire diameter according to relevant regulation.

With Power Facility

Outdoor power
supply
380~415V 3N~
50Hz

Leakage protector

Leakage protector
Manual switch

Junction part

Outdoor
unit

Outdoor
unit

Outdoor
unit

Outdoor
unit

Outdoor
unit

Outdoor
unit

Manual
switch

Grounding

Grounding

Grounding

Grounding

Grounding

Grounding

( a )

(b)

(b)

Junction part

Power facility
(with leakage protector)

Outdoor

unit

Outdoor

unit

Manual switch( A )

Grounding

Grounding

Grounding

Grounding

Grounding

Grounding

The power wiring is the mainline (a) to the junction box and
the wiring (b) from the junction box to power facility. Please
choose as following:

(1) Diameter of the mainline (a)
Index Table 2: the sum of the outdoor unit horsepower.
For example: (5 horsepower X 1 unit + 8 horsepower X1

unit + 10 horsepower X 1 unit) = 23 horsepower (The total horsepower)

2

(table.2) wire diameter=60mm (50m below)

(2) Wire diameter(b) between junction box and power

Facility
When the assembled outdoor units is 5 or less, the same
with the mainline. When the group is up to 6 or more, the
control box of the power facility will be divided
into two, and index Table 2 with the sum of the outdoor unit
horsepower.

Choose the wire diameter

2

Choose wire diameter (not less than)(Unit: mm )

10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30

31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50

9
9
13
13
13
13
23
23
23
23
23
23
36
36
36
36
36
36
36
60
60

60
60
60
60
60
60
60
60
60
90
90
90
90
90
90
90
90
90
90
90

60
60
60
60
60
60
90
90
90
90
90
90
90
90
90
90
90
90
90
90

23
23
23
23
36
36
36
36
36
36
36
36
60
60
60
60
60
60
60
60
60

Sum of
Horsepower

Sum of
Horsepower

20m or less 20m or less

Wire length is Wire length isWire length is Wire length is

50m or less 50m or less

Choose the manual switch and fuse capacity for junction box.

(1) Decided by the connected outdoor unit (See Table 1),

when power facility is not concerned.

(2) As concerning to the power facility, according to the outdoor

unit horsepower sum to choose .(See Table 3)

Sum of Horsepower, Manual Switch and Fuse capacity List

(Table 3)

10~14

100 75

15~18

100 100

19~28

150 150

Sum of Horsepower

Manual Switch (A) Fuse (A)

29~36

200 200

37~47

300 250

48~50

300 300

Sum of Horsepower

Manual Switch (A) Fuse (A)

POWER WIRING

< Indoor Unit Wiring>

Power Supply (Table 1)

NOTE: The wire diameter and continuous length is under the
condition that the voltage vibration is within 2%. If the
continuous length is exceed the showing value, choose
the wire diameter follow relevant regulation.

Single Phase 220-240V~ 50Hz
Current leakage Protector

Manual Switch

Wire Distribution Box

Indoor Unit

Indoor Power Supply

1

9

2103

11

4

12

5

13

6

14

7

1515

8

1616

CAUTION

1. Refrigerant piping system indoor unit-indoor unit connection
signal wires and indoor unit-outdoor unit connection signal wire
are in the same system.

2. When power cord is parallel with signal wire, please put
them into separate wire distribution pipes, and leave a proper
distance.
(Reference distance: It is 300mm when current capacity of
power cord is less than 10A, or 500mm when 50A).

Please use shield wire as indoor unit/outdoor unit signal
wire.

Indoor/Outdoor unit signal wire wiring

TEST RUNNING

Operate according to "gist for test running" on the electric control
box cover

CAUTION:

Test running can not start until the outdoor unit has been
connected to the power for 12hr.
Test running can not start until all the valves are affirmed open.
Never make the forced running .(Or the protector sits back ,
danger will occur.)

FILL THE NAME OF CONNECTION SYSTEM

To clearly identify the connection systems between two or
more indoor unit and outdoor unit, selects names for every
system and records them on the nameplate on the outdoor
electric control box cover.

PRECAUTION ON REFRIGERANT LEAK

A[kg]

3

B[m ]

This air conditioner (A/C) adopts R407C or R22 as refrigerant,
which is innocuous and nonflammable. The locating room of
the A/C should big enough that any refrigerant leakage is unable
to reach critical thickness. So certain essential action can be
taken on time.

Critical thickness------the Max. thickness of Freon without
any harm to person.

3

Refrigerant critical thickness: 0.3[kg/m ]
Confirm the critical thickness through follow steps, and take
necessary actions.

1. Calculate the sum of the charge volume (A[kg]) Total
Refrigerant volume of 10HP= factory refrigerant volume +
superaddition

3

2. Calculate the indoor cubage (B[m ]) (as the minimum
cubage)

3. Calculate the refrigerant thickness

Countermeasure against over high thickness

1. Install mechanical ventilator to reduce the refrigerant thic­ kness under critical level. (ventilate regularly)

2. Install leak alarm facility related to mechanical ventilator if
you can not regularly ventilate.)

3

critical thickness: 0.3[kg/m ]

b. Leak alarm related to mechanical ventilator

A. Ventilation
peristome

(Leak hunting siren should be installed
in places easily keep refrigerant)

Indoor unit

Outdoor unit

Indoor
unit

Room full of leak refrigerant

(All refrigerant has run up)

The owner's manual of indoor unit and owner's manual of
outdoor unit must be turned over to the customer.
Explain the contents in the owner's manual to the customers
in details.

TURN OVER TO CUSTOMER

Indoor/Outdoor unit signal wire is low voltage circuit.
Do not let it touch the high voltage power wire and put
it to gather with power cord in the same wire distribution pipe.

CAUTION

Wire Size and Quantity

1. Signal wire is 2-core, polarized wire. Use 2-core shield wire
to prevent interference from outdoor. The grounding method
now is grounding the closed end of the shield wire and
opening (insulating) at the end. One point on outdoor side
is to be grounded.

2. The control between outdoor unit and indoor unit is
BUS type. Addresses is set on field during the installation.

Leakage protector

Table 2

OUTDOOR UNIT INSTALLATION

1. A 10mm distance should be left
between outdoor units.

M12 Foot screw 4Pieces per unit

<650mm

Type

Size

A
B
C

10HP 20HP

30HP

1030

1030

2025

55

2025

3020

55

3020

The power supply of 20HP or 30HP is separated. Each item supply please refer to above MDV-D280W/SN2 .