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
In
do
or
U
ni
t t
o
In
do
or
U
ni
t
D
ro
p
H
ei
gh
t
Maximum Piping Equivalent Length L 125m
(From the first Line branch pipe) Maximum piping
Equivalent Length L 40m
Header Branch Pipe
D
ro
p
H
ei
gh
t b
et
w
ee
n
In
do
or
un
it
an
d
ou
td
oo
r
U
ni
t
H
50
m
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 distribu-
tor (branch connection, header branch
pipe) should be used in the process or
refrigerant piping.
Refrigerant piping should meet the specifi-
ed 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 vacuum-
ing 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 exa-
mple) 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
f
28.6
(
Welding
)
f
38.0
(
Welding
)
f
45.0
(
Welding
)
f
12.7
(
Flaring nut
)
f
19.0
(
Flaring nut
)
f
22.0
(
Welding
)
1. Table 1
Piping sizes and connecting method of the
outdoor unit.
MDV-D280W/SN
2
MDV-D280W/S
MDV-D560W/SN
2
MDV-D560W/S
MDV-D840W/SN
2
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
L
1
+L
2
+L
3
+L
4
+L
5
+L
6
+L
7
L
1
+L
3
+L
4
+L
5
+L
6
+j
L
3
+L
4
+L
5
+L
6
+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
P
ip
e
L
e
n
g
th
D
ro
p
H
e
ig
h
t
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 (
f
6mm 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/SN
2
MDV-D560W/SN
2
MDV-D840W/SN
2
MDV-D280W/S(N
2
)
MDV-D560W/S(N
2
)
MDV-D840W/S(N
2
)
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.
f
19.0(Flaring nut)
f
9.5(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
22
33
22
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 oxidiz-
ing inside when welding, it is necessary to
charge nitrogen, or oxide will choke the
circulation system.
CAUTION:
