MDV-D Installation
c! Installation
1� Summarize of Installation & & & & & & & & & & & & & . & & & & ....240
2� Installation of Outdoor unit & & & & & & & & & & & & & & & ..& ... .242
3� Installation of Indoor unit & & & & & & & & & & & & & . & & & & & .243
4� Installation of Refrigerant Pipe & & & & & & & & & ..& . & & & & & .244
4.1 The permitted length and drop difference of refrigerant pipe& & & ...244
4.2 Pipe size selection& & & & & & & & & & & & & & & & & & & & & ....246
4.3 Precautions& & & & & & & & & & & & & & & & & & & & & & & .& 249
4.4Dimension of Refrigerant Distributor& & & & & & & .& & & & & & ..251
4.5 Installation work of Refrigerant pipe& & & & & & & & & & & ...& & 252
4.6 Additional Charge of Refrigerant& & & & & & & & & & & & & & & .262
5� Processing & Installation of Drainage Pipe& & & & & & & & & & .& ..263
6� Installation Work& & & & ..& & & ...& & & ..& & & & & & & & & & ...266
7� Pipeline Installation& & & & ..& & & & & & & & & & & & & & & & & 268
8� Electric Installation& & & & ..& & & & & & & .& .& .& & & & & & & ..272
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MDV-D Installation
1� Summarize of Installation
1.1 Installation Procedure
Confirm project, Sign contract
Audit shop drawing
Install indoor unit Make foundation of outdoor unit
Install outdoor unit
Install refrigerant pipe
Pressure test
Install drainage pipe
Vacuum dry for refrigerant pipe
Pipeline making and installation
Additional charge of refrigerant
Install decorative panel
Test run and debugging
Check and accept
1.2 Install indoor units
Procedure:
Label installation position Install hook Install indoor unit
Confirm installation position
Note�1.The hook must strong enough to sustain the weight of indoor unit.
2.Check the models of indoor units before installation.
3.Pay attention to the main devices, such as the pipeline.
4.Obligate enough place for maintenance.
5.Obligate check point (400x400).
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MDV-D Installation
1.3 Refrigerant pipe
Procedure:
Permute Nitrogen
Install indoor unit Install pipe Solder
Temporary pipeline Blow
Pressure test Vacuum dry
1.4 Drainage pipe
Procedure:
Install indoor unit Connect drain pipe Check water leakage Drain pipe heat-insulation
1.5 Electric wiring
1. Control wire: please pay attention to the consistency. When wiring parallel to the power wire, please
keep certain distance(300mm) to prevent interfering signal.
2. Power wire: please pay attention to select correctly the breaker switch, dimension of wire, and so on.
And both indoor units and outdoor units should be grounded well. The power wire and signal wire can t
be enlaced together.
1.6 Lay the indoor pipeline
Note: Collocate the air-outlet reasonably to prevent airflow short-circuit. Check the static pressure is in the
allowable range. The air filters are easily to unpick and wash. Do pressure test on pipeline.
1.7 Heat-insulation
Procedure:
Refrigerant pipe work Test the heat-insulated part Pressure test Heat-insulation work
Note: For welding part, flare part and branch pip, heat-insulation work must be done after finishing pressure test.
1.8 Install outdoor unit
Procedure:
Heat-insulation work Install outdoor unit
Note: 1. Gutter must be set around the foundation to drain out the accumulated water.
2. When installing outdoor units at the housetop, please check the strength of the housetop and pay
attention not to destroy the waterproof of the housetop.
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MDV-D Installation
1.9 Recharge refrigerant
Procedure:
Calculate the added volume according to liquid pipe length Recharge refrigerant
Note: the calculation results must be correct.
1.10 Main points of test running and debugging
Examine the following before turning on the power: Vacuum dry, power wiring, control wiring, additional
charge of refrigerant, open the close-valve of gas pipe, open the close-valve of liquid pipe, test insulation.
Measure the indoor temperature in cooling mode and heating mode. Measure air-inlet temperature and discharge
temperature.
Measure the following for outdoor unit: insulation resistance, voltage, current, discharge pressure, air-inlet
pressure, discharge pipe temperature, air-inlet pipe temperature, compressor frequency.
2� Installation of Outdoor unit
2.1 Hanging and Transportation
(1) Sling the outdoor unit and carry it in with 4 steel wire (Ć6mm or more)
(2) Use soft board to protect the unit surface from scratch and distortion where contact the steel wire.
Steel wire
Protect board
Base board
2.2 Required Installation Place and Installation Dimension
Please refer to the Outdoor Units.
242
20
MDV-D Installation
3� Installation of Indoor unit
2.1 Hanging and Transportation
Please refer to Indoor unit Installation Manual.
2.2 Required Installation Place
(1) Cassette Type
A B C
One-way Cassette
1000mm above
Four-way Cassette 1000mm above 2300mm above
(2) Duct Type
(3) Wall Mounted Type
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MDV-D Installation
4� Installation of Refrigerant Pipe
4.1 The permitted length and drop difference of refrigerant pipe
t$ 10~30HP
L2
L1
L6
L5
L4
i
Permitted length Pipe
d"250m(less than 54kW)
Pipe total length (actual length) L1+L2+L3+L4+L5+L6+L7+a+b+& i
d"300m(above 54kW)
Pipe
Actual length d"100m
Farthest pipe length�m � L1+L3+L4+L5+L6+i
length
Equivalent length d"125m
Equivalent length L of pipe from the first branch
d"40m L3+L4+L5+L6+i
to the farthest one �m �
Above outdoor unit d"50m  
Drop height between indoor
Drop
unit and outdoor unit
Below outdoor unit d"30m  
height
Drop height between indoor unit and indoor unit
d"15m  
; Conversion of the equivalent length: Convert into the direct pipe length
according to branch Junction 0.5m/l and branch header pipe 1.0m/l.
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MDV-D Installation
u$ 4~6HP
Outdoor Unit
1
3
2
The first line branch pipe
2
2 2
3
3 3 3 3
Permitted
Pipe
length
L1+L2+L3+L4+L5+L6+L7+a+b+
Pipe total length(actual length) d"100m
c+d+e
60m(140W)or
Actual length
Pipe
45m (1100W)
Farthest pipe length(m) L1+L3+L4+L5+L6+e
length
70m(140W)or
Equivalent length
50m (100W)
Equivalent length L of pipe from the first branch
d"20m L3+L4+L5+L6+e
to the farthest one(m)
Above outdoor unit d"20m  
Drop height between
Drop
indoor and outdoor unit
Below outdoor unit d"20m  
length
Drop height between indoor unit and indoor unit d"8m  
Pipe
Main pipe�D1=ą�19.0 D3=ą�9.5 Branch pipe�D2=ą�15.9 D4=ą�9.5
O.D
; Conversion of the equivalent length: Convert into the direct pipe length according to branch Junction 0.5m/l
and branch header pipe 1.0m/l.
Outdoor Unit (one or more ou tdoor un its)
2
1
The first Line Branch Pipe
I ndoor Unit
3
Ma ximu m Piping Equi valen t Leng th L
(Fr om the f r st Line branch pipe) Maximum p pi
i i ng
e c
Equival Length L 20m
ent
H 8m
5 6
4
F
G
H I
J
Indo or Un it
245
n
Drop Height between Indoor
unit and outdoor Unit H 50m
Indoor Unit to Indoor U it
Drop Hei ght
MDV-D Installation
4.2 Pipe size selection
4.2.1 The selection of the refrigerant pipe
Type of the pipe Connecting part No.
Between outdoor unit and the first branch part
Main pipe 1 2
Between the branch part and branch part
Branch pipe Between the branch part and indoor unit 3
Outdoor Unit
Branch Joint
2 2
2
1 2 2
Indoor Unit
3 3 3 3 3 3
Controller
Outdoor Unit
Invergent Branch
1
Indoor Unit 3 3 3 3
Indoor Unit
Controller
Outdoor Unit
Branch Joint
2
2
2
1
3 3 3
Indoor Unit
3 3 3 3
Controller
4.2.2 Dimensions of the main and branch pipes
t$ 4~6 HP
gas side liquid side
Dimensions of the main pipe Ś19.0 Ś9.5
Dimensions of the Branch pipe Ś19.0 Ś9.5
u$ 10~30 HP
Dimensions of the main pipe Dimensions of the Branch pipe
A (hr)
(gas/liquid side) (gas/liquid side)
Ad" 10 Ś28.6/Ś12.7
1020Notes: A means the horsepower sum of the all indoor units which are below the main pipe.
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MDV-D Installation
Indoor and outdoor unit pipes dimensions
Model MDV- D22 ~ D140 D100(140)W/S(N2) D280W/S(N2) D560W/S(N2) D840W/S(N2)
Gas Ś19.0 Ś19.0 Ś28.6 Ś38.0 Ś45.0
Liquid Ś9.5 Ś9.5 Ś12.7 Ś19.0 Ś22.0
Notes:
1. The main pipe dimension is consistent with that of the outdoor unit;
2. The branch pipe dimension is consistent with that of the indoor units.
4.2.3 Selecting Branch Type
t$ 4~6HP
Model
Branch joint
MDV-BY51 or MDV-BY101
(2-branch junction)
u$ 10~30HP
Dimensions of the main pipe
Branch part
(gas/liquid side)
Ś28.6/Ś12.7 MDV-BY101
Ś38.0/Ś19.0 MDV-BY102
Ś45.0/Ś22.0 MDV-BY103
4.2.4 Connecting method
t$ 4~6HP
Gas side Liquid side
Outdoor unit Flaring nut Flaring nut
Indoor unit Flaring nut Flaring nut
Branch part Welding Welding
BS device Flaring nut Flaring nut
u$ 10~30HP
Gas side Liquid side
10HP Outdoor unit Welding Flaring nut
20HP Outdoor unit Welding Flaring nut
30HP Outdoor unit Welding Welding
Indoor unit Flaring nut Flaring nut
Branch part Welding Welding
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MDV-D Installation
4.2.5 Example as 10~30HP
t$ Selecting the refrigerant pipe
Type of pipe No.
Main pipe `$or a$ e$
Branch pipe7 13
u$ Selecting the dimension of main pipe
Indoor units below Total HP of indoor units Pipe dimension
No. A (hr)
main pipe below main pipe (Gas/Liquid)
`$ main pipe 1# 7# 5�5+3+2=30 (HP)
20a$ main pipe 2# 7# 4�5+3+2=25 (HP)
b$ main pipe 3# 7# 3�5+3+2=20 (HP)
10c$ main pipe 4# 7# 2�5+3+2=15 (HP)
d$ main pipe 5# 7# 5+3+2=10 (HP) Ad" 10
Ś28.6/Ś12.7
e$ main pipe 6# 7# 5+2=7 (HP) Ad" 10
v$ Selecting the dimension of branch pipe
Branch pipe Pipe dimension (Gas/Liquid)
7 13 Ś19.0/Ś9.5
w$ Selecting branch joint
Branch part Model
a
MDV-BY103
b
c
MDV-BY102
d
e
MDV-BY101
f
x$ Selecting connection method
Gas side Liquid side
30HP Outdoor unit Welding Welding
Indoor unit Flaring nut Flaring nut
Branch part( a f ) Welding Welding
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MDV-D Installation
4.3 Precautions:
4.3.1 Refrigerant pipe must use the pipe with specified diameter.
4.3.2 Branch Junction could be installed in horizontal mode or vertical mode.
HORIZONTAL
LINE
A direction
OR
within ą30�
HORIZONTAL
LINE
B direction
4.3.3 Branch converging pipe must be installed in horizontal direction
Refrigerant Distributor
(gas side) Refrigerant Distributor
(liquid side)
B direction
B direction
HORIZONTAL LINE
B direction
B direction
4.3.4 Branch converging pipe is connected to the indoor unit and no more branch is allowed after one branch
converging pipe.
249
A
B
T
I
N
U
T
I
R
N
O
U
O
R
D
O
N
I
O
O
D
T
T
N
I
O
T
MDV-D Installation
outdoor unit
Branch Converging Pipe
wrong connection
wrong connection
wrong connection
indoor unit
controllor
4.3.5 Electric throttle kit must be installed vertically
Electric throttle kit must
Electric expand valve
be placed vertically
To outdoor unit
To indoor unit
4.3.6 Refrigerant fastness, the Refrigerant fastness, the distance between the support of the cross direction tube
(copper tube):
Nominal diameter Below 16 16 25 Above 32
Max. distance (m) 1.0 1.5 2.0
4.3.7 Calculation of the pipe length
t$ Available length of pipe =pipe length + the amounts of branch � branch equivalent length +the amounts
of elbow � elbow equivalent length.
u$ Conversion of the branch equivalent length: convert into the direct pipe length according to branch
Junction 0.5m/l and branch header pipe 1.0m/l.
v$ Conversion of elbow equivalent length.
Gas pipe dimension Ś12.7 Ś15.9 Ś19.0 Ś25.4 Ś28.6
Junction(90�elbow) 0.10 0.10 0.15 0.15 0.20
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MDV-D Installation
4.4 Dimension of refrigerant distributor
1) BY51 2) BY101
3) BY102 4) BY103
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MDV-D Installation
4.5 Installation work of Refrigerant pipe
4.5.1 Protection of Refrigerant pipe material
t$ Transportation and storing of refrigerant pipe
When transporting the pipes, please protect the pipes from wending and distortion. Please place a cap at
the open end of the pipe in order to prevent water and mud entering, and store in the appointed site.
u$ All the open ends of the pipes need to be protected. The best feasible means is Enveloping End, and you can
select the easy means of Wrapping. Refer to the following table to select the means used in different sites.
Site Period Maintenance Means
Above three months Envelop End
Outdoor
Below three months Envelop End or Wrapping
Indoor No limit Envelop End or Wrapping
`$ Envelop End: Welding the leak while clamping the end of the pipe.
a$ Wrapping: Wrapping the pipe with polyethylene insulation tape.
b$ The following operation should be noted:
When putting the pipe through the hole, filth can easily enter into the pipe.
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MDV-D Installation
When the pipe is outside, rainwater can easily enter into the pip, especially when the pipe is
placed vertically.
v$ Precautions:
`$ Protect the open end of the pipe against moisture, dust and litter.
Before finishing pipe connection, place a cap at the open end of the pipe.
Try to make the open end of the pipe thwart or downward.
a$ A cap must be placed on the end of the pipe when the pipe crosses the hole in the wall.
b$ Don t place the pipe on the ground directly or scratch with the ground.
c$ Cut the pipe and remove burrs with the cut surface downward.
d$ Be sure to place a cap when raining.
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MDV-D Installation
4.5.2 Welding
t$ Be sure to weld horizontally or downward, not upward.
u$ Pay attention to the installation direction and angle to prevent oil-return or oil-accumulation..
v$ It s necessary to charge nitrogen when welding.
`$ Be far away from fire and prepare fire extinguishers and water to prevent fire on field.
a$ Be careful not to injure people.
b$ Confirm the proper clearance between pipe and connector..
c$ Check if the supporting structural members are strong enough.
The traverse distances between supporting structural members are as follows:
Diameter (mm) Below 20 25~40 50
Max. Distance (m) 1.0 1.5 2.9

Min. inserting depth and clearance between connectors.
Unit: mm
Out .Diameter. (D) Min. Inserting depth (B) Clearance (A~D)
5�D�8 6
0.050~0.21
8�D�12 7
11�D�16 8
0.050~0.27
16�D�25 10
25�D�35 12
0.050~0.35
35�D�45 14
4.5.3 Flare Connection
t$ Before flaring, the auxiliary pipe must be annealed.
u$ Use incision machine.
254
A
D
MDV-D Installation
v$ Dimension:
Shape Diameter O.D. A
3/8" 9.53
0.05 0.21
1/2" 12.7
5/8" 15.88
0.05 0.27
3/4" 19.05
w$ Smear oil at flaring part.
`$ Be careful to get rid of burr.
a$ Use two torques.
b$ Use proper torque to fasten nut.
Torque
Dimension
(kgf �m) (N�cm)
1/4"(Ś6.4) 144 176 1440 1720
3/8"(Ś9.5) 133 407 3270 3990
1/2"(Ś12.7) 504 616 4950 6030
5/8"(Ś15.9) 630 770 6180 7540
3/4"(Ś19.0) 990 1210 9270 11860
4.5.4 Laying
t$ Laying the refrigerant pipes
`$ Mark the system clearly in every distance to prevent wrong connection.
a$ The plane where the two branches locate should be parallel to the horizontal plane, or the main pipe of the
branch pipe is vertical to the horizontal plane, which can avoid bad effect due to uneven distribution of gas and
liquid.
u$ Protection of outdoor refrigerant pipes
Sudden damnification also should be considered except heat-insulated layer. If the length of bare part is over
1m, a buckle-board must be added to the bare part.
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MDV-D Installation
v$ Laying principle of MDV refrigerant pipes
`$ Centralized laying, laying along the wall, and trying to make full of use of corridor.
a$ After finishing laying, binding up the refrigerant pipes with white binding-strap. After finishing winding-up
every pipe separately, please try to binding up all pipes together according to the diameters and the degree of
tightness should be based on no feeling of flexible.
b$ When installing the connection pipes and electric wires(power wire, control wire), they should be laid along
the wall, turn the corner logically, flat and straight, parallel with each other and packed together. And try to avoid
striding over and blocking the traffic.
c$ The connection pipes and electric wires should be as short as possible.
d$ Try to bind up all pipes and no bareness is allowed at the connecting part.
w$ Precautions about laying refrigerant pipes
`$ Pulling pipe: mark the system No. in the pipes to prevent wrong connection.
a$ Make sure the support of the pipes is firm enough.
(5) Requirements of protection and appearance
4.5.5 Refrigerant pipe Flushing
Refrigerant pipe flushing is a method to eliminate filter. It has three main functions:
When nitrogen is insufficient, flushing can eliminate oxide air bubble.
When the end of the pipe can t sealed well, flushing can eliminate filter and humidity.
Flushing can check the indoor/outdoor pipe connection.
Main procedure is as the following:
(1) Install pressure modulation valve at the nitrogen cylinder. And the gas used must be nitrogen. Carbon Dioxide
will probably condense. And Oxygen will probably cause explosion.
(2) Use charge pipe to connect pressure modulation valve and outdoor liquid pipe.
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MDV-D Installation
(3) Jam well all the connection part in liquid side except indoor unit A.
(4) Open the valve of nitrogen cylinder to 5kgf/cm2.
(5) Check if there is nitrogen in liquid pipe of indoor unit A.
(6) Flushing
`$ Use the insulating material in hand to resist the nozzle of gas main pipe of the indoor unit.
a$ When the pressure can t be resisted, release the insulating material quickly (flushing for the first time), then
use the insulating material to resist the nozzle again (flushing for the second time).
b$ The dunghill can be checked by putting a piece of cloth in the nozzle loosely. Occasionally, some dampness
can be found, please dry the pipe thoroughly. Do as follows:
Scouring the inner part of the pipes with nitrogen until no dampness.
Do the vacuum drying procedure(see the MDV refrigerant pipes vacuum drying in detail)
(7) Close the nitrogen main valve.
(8) Repeat the above operations.
(9) After finishing flushing the liquid pipes, then flushing the gas pipes.
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MDV-D Installation
4.5.6 Refrigerant pipe Pressure Test
t$ Adding pressure operation
`$ During pressure test, the valves on gas side and liquid side should be full-closed.
Because nitrogen may enter into the outdoor circulation system, strengthening the valves before
adding pressure operation.
a$ For every refrigerant system, add pressure slowly and orderly from gas and liquid side.
b$ And the gas used must be nitrogen. Carbon Dioxide will probably condense. And Oxygen will
probably cause explosion.
c$ The time must be over 24h in the third-phase of adding pressure.
d$ Sketch map of adding pressure.
u$ Control diagram for adding pressure by stages
No. Phase (add pressure by stages) Standard
Add pressure 3.0kgf/cm2G for more than 3 minutes to check big leakage.
1
No pressure falling
2 Add pressure 15.0kgf/cm2G for more than 3 minutes to check big leakage.
3 Add pressure 28.0kgf/cm2G for more than 24 hours to check small leakage.
v$ Observe the pressure
`$ Add pressure 28.0kgf/cm2G for more than 24 hours, pass if there s no pressure falling. If the pressure falls,
it should be corrected. After that, if the pressure is still lower than that when adding pressure, the leakage should
be checked out and corrected.
a$ Correcting method
If there s 1! difference in temperature, there will be 0.1 kgf/cm2 difference in pressure.
Correcting formula: actual value = pressure in the stage of adding pressure +(temperature in the stage of
258
MDV-D Installation
adding pressure  observed temperature ) x 0.1 kgf/cm2
Compare the correcting value and adding pressure value to see whether the pressure falls.
b$ Look up the leakage point in three phases when the pressure falls.
Check the leakage by ears---can hear loud noise of the leakage.
Check the leakage by hands---put the hands in the pipe connection to check the leakage.
Check the leakage by suds---the leakage point will emit air bubble.
Check the leakage by halogen detector.
Use halogen detector when finding the tiny leakage point or pressure falls but no leakage point can be
found during the adding pressure test.
Place the nitrogen under 3.0 kgf/cm2
Add fluorin to the point 5.0 kgf/cm2 (mixed state of fluorin and nitrogen).
Check by halogen detector, alkyl detector, electric detector and so on.
If no leakage can be found, continue to add pressure to 28.0 kgf/cm2 , then check again.
w$ Precautions
`$ The maximum pressure in gas proof test should not exceed 28.0 kgf/cm2
a$ If the pipe is too long, check by sections.
Indoor side
Indoor side + Vertical pipe
Indoor side+ Vertical pipe +Outdoor side
4.5.7 Vacuum Dry for Refrigerant pipe
t$ Vacuum Dry: use vacuum pump to change the moisture (liquid) into steam (gas) in the pipe and discharge it
out of the pipe to make the pipe dry. Under one atmospheric pressure, the boiling point of water(steam
temperature) is 100!. Use vacuum pump to make the pressure in the pipe near vacuum state, the boiling point of
water falls relatively. When it falls under outdoor temperature, the moisture in the pipe will be vaporized.
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MDV-D Installation
u$ Selection of vacuum pump
`$ Select the vacuum pump. (Normally the anticipative demand achieves -755mmHg)
a$ Big discharge volume (over 40l/min). Check the vacuum calculator before operation to make
sure its measure range achieve below -755mmHg.
Boiling point of water(!) Gas pressure (mmHg) Vacuum degree (mmHg)
40 55 -705
30 36 -724
26.7 25 -735
24.4 23 -737
22.2 20 -740
20.6 18 -742
17.8 15 -745
15.0 13 -747
11.7 10 -750
7.2 8 -752
0 5 -755
v$ Vacuum dry procedure
There are two methods of vacuum dry due to different construction environment: common vacuum dry,
special vacuum dry.
`$ Common vacuum dry procedure
Vacuum dry (for the first time)---connect the all-purpose detector to the inlet of liquid pipe
and gas pipe, and run the vacuum pump more than two hours (the vacuum pump should be
below -755mmHg)
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MDV-D Installation
If the pump can t achieve below -755mmHg after pumping 2 hours, moisture or leakage point
will still exist in the pipe. At this time, it should be pumped 1 hour more.
If the pump can t achieve -755mmHg after pumping 3 hours, please check if there s some
leakage points.
Vacuum placement test: place 1 hour when it achieves -755mmHg, pass if the vacuum watch
shows no rising. If it rises, it shows there s moisture or leakage point.
Vacuuming from liquid pipe and gas pipe at the same time.
Sketch map of common vacuum dry procedure.
a$ Special vacuum dry procedure
This vacuum dry method is used in the following conditions:
There s moisture when flushing the refrigerant pipe.
Rainwater may enter into the pipe.
Vacuum dry for the first time ������ 2h pumping
b$ Vacuum destroy for the second time ������ Fill nitrogen to 0.5Kgf/cm2
Because nitrogen is for drying gas, it has vacuum drying effect during vacuum destroy. But if
the moisture is too much, this method can t dry thoroughly. So, please pay more attention to
prevent water entering and forming condensation water.
c$ Vacuum dry for the second time������1h pumping
Determinant: Pass if achieving below -755mmHg. If -755mmHg can t be achieved in 2h, repeat
procedureb$and c$.
d$ Vacuum placing test ������ 1h
e$ Sketch map of special vacuum dry procedure
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MDV-D Installation
4.6 Additional Charge of Refrigerant
Procedure
Calculate refrigerant volume according to liquid pipe length Refill refrigerant
`$ The refrigerant needed by the pipes installed on fields is not filled in the factory. After finishing
installation, add refrigerant when the length of liquid pipe on field is over 0m.
a$ Calculation
Refill volume (kg) = (L1�0.065 kgf/cm2) + (L2�0.115 kgf/cm2) +
(L3�0.290 kgf/cm2 ) + (L4�0.380 kgf/cm2 )
In the above formula: L1 Ś9.5 Total real length of liquid pipe (m)

L2 Ś12.7 Total real length of liquid pipe (m)
L3 Ś19.0 Total real length of liquid pipe (m)
L4 Ś22.0 Total real length of liquid pipe (m)
Write the added volume in the outdoor nameplate.
The added volume must be measured with electron scale.
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MDV-D Installation
5. Processing &Installation of Drainage Pipe
5.1 Gradient and Supporting
t$ Keep the drainpipe sloping downwards at a gradient of at least 1/100. Keep the drainpipe as short as
possible and eliminate the air bubble.
u$ The horizontal drainpipe should be short. When the pipe is too long, a prop stand must be installed to keep
the gradient of 1/100 and prevent bending. Refer to the following table for the specification of the prop
stand.
Diameter Distance between the prop stands
Hard PVC pipe 25~40mm 1.5~2m
v$ Precautions
`$ The diameter of drainpipe should meet the drainage requirement at least.
a$ the drainpipe should be heat-insulated to prevent atomization.
b$ Drainpipe should be installed before installing indoor unit. After powering on, there is some water in
water-receiver plate. Please check if the drain pump can act correctly.
c$ All connection should be firm.
d$ Wipe color on PVC pipe to note connection.
e$ Climbing, horizontal and bending conditions are prohibited.
f$The dimension of drainpipe can t less than the connecting dimension of indoor drainpipe.
g$ Heat-insulation should be done well to prevent condensation.
h$Indoor units with different drainage type can t share one convergent drainpipe.
5.2 Drainpipe Trap
t$ If the pressure at the connection of the drainpipe is negative, it needs to design drainpipe trap.
u$ Every indoor unit needs one drainpipe trap.
v$ A plug should be designed to do cleaning.
Plug
5.3 Upwards drainage(drain pump)
t$ To ensure the gradient 1/100, the drainpipe can be lifted to 340mm. After upwards, place downwards, or it
263
50cm
50cm
MDV-D Installation
will cause malfunction to drain pump.
5.4 Convergent drainage
t$ The number of indoor units should be as small as possible to prevent the traverse main pipe overlong.
u$ Indoor unit with drain pump and indoor unit without drain pump should be in different drainage system.
v$ Selecting the diameter
Number of connecting indoor unitsCalculate drainage volumeSelect the diameter
Calculate allowed volume =Total cooling capacity of indoor units(HP)�2 (l/ hr)
Allowed volume(lean 1/100) (l/ hr) I.D. (mm) Thick
Hard PVC ="d"14 ą�25 3.0
Hard PVC 14�="d"88 ą�30 3.5
Hard PVC 88�="d"334 ą�40 4.0
Hard PVC 175�="d"334 ą�50 4.5
Hard PVC 334�=" ą�80 6.0
5.5 Drainage test
t$ Drainage without drain pump
After finishing drainpipe installation, pour some water into the water receiver plate to check if the water
flows smoothly.
u$ Drainage with drain pump
`$ Poke the Water Level Switch , remove the cover, use water pipe to pour 2000ml water into the water
receipt plate through the water inlet.
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a$ Turn on the power to Cooling operation. Check the pump s operation and switch on the Water Level
Switch. Check the pump s sound and look into the transparent hard pipe in the outlet at the same time
to check if the water can discharge normally.
b$ Stop the air conditioner running, turn off the power, and put back the cover.
Stop the air conditioner. After 3 minutes, check if it has abnormity. If the collocation of drainpipes
is illogical, the water will flow back overfull, which will cause the alarm lamp flashes, even
overflow from the water receipt plate.
Keep on pouring water until it gives an alarm signal for high water level, check if the pump drains
water at once. If the water level can t fall below the alarmed water level after 3 minutes, the air
conditioner will stop. Turn off the power and drain the remained water , then turn on the air
conditioner.
Note: the drain stuff in the main water receipt plate is for maintenance. Stuff up the drain stuff to
prevent water leakage.
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6. MDV Insulation Work
6.1 Insulation material and thickness
(1) Insulation material
Insulation material should adopt the material which is able to endure the pipe s temperature: no less than 70!
in the high-pressure side, no less than 120! in the low-pressure side(For the cooling type machine, no
requirements at the low-pressure side.)
Example: Heat pump type----Heat-resistant Polyethylene foam (withstand above 120!)
Cooling only type---- Polyethylene foam (withstand above 100!)
(2)Thickness choice for insulation material
Insulation material thickness is as follows:
Pipe diameter (mm) Adiabatic material thickness
Ś6.4 Ś25.4 10mm
Refrigerant pipe
Ś28.6 Ś38.1 15mm
Drainage pipe
Inner diameterŚ20 Ś32 6mm
6.2 Refrigerant pipe insulation
(1) Work Procedure
`$ Before laying the pipes, the non-jointing parts and non-connection parts should be heat insulated.
a$ After the gas proof test is eligible, the jointing area, expanding area and the flange area should be heat
insulated
(2) Insulation for non-jointing parts and non-connection parts
wrong right
Gas pipe and liquid pipe should Insulate the gas pipe Insulate the gas pipe and
not be put together to insulate (cooling only) the liquid pipe
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For construction convenience, before laying pipes, use insulation material to insulate the pipes to be deal
with, at the same time, at two ends of the pipe, remain some length not to be insulated, in order to be welded and
check the leakage after laying the pipes.
(3) Insulate for the jointing area, expanding area and the flange area
`$ Insulate for the jointing area, expanding area and the flange area should be done after checking leakage of
the pipes
a$ Make sure there s no clearance in the joining part of the accessorial insulation material and local
preparative insulation material.
(4) Enswathe disposal
After insulation of the pipes, do the enswathe disposal with binding belt, make sure it s tight.
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6.3 Drainage pipe insulation
(1) The connection part should be insulated, or else water will be condensing at the non-insulation part.
6.4 Note
(1) The jointing area, expanding area and the flange area should be heat insulated after passing the pressure test
(2) The gas and liquid pipe should be heat insulated individually, the connecting part should be heat insulated
individually.
(3) Use the attached heat-insulation material to insulate the pipe connections (pipes tie-in ,expand nut ) of the
indoor unit.
7. Pipeline Installation
7.1 Pipeline facture
(1) The material of the pipeline
Standard: lubricity inside, small friction resistance, not absorbing moisture, incombustibility, erosion
resistance, longevity, lightness, good sealing, no accumulation, easily cleaning. Normally, we can select
galvanization steel, aluminum, and plastic. For short pipeline, we can also select aluminum foil board.
(2) The process of the piping
The process of the piping should meet the requirements of the design. The process can be done in
subsection. And every subsection s length is about between 1.8m and 4m. In order to improve the
pipeline s rigid, a rib often be added at the outer surface. The pipeline usually adopts the flange to
connect and add the asbestos washer with thickness 3mm to prevent air leakage. At present, the sealant
and adhesive tape are also used to seal.
(3) The shape of the pipeline
`$Type of the pipeline
The pipeline has ground and direct shape. The compare is as follows:
Ground pipeline Square pipeline
need small space, can be equipped easily,
less material, need large space, its bending
adopt direct pipeline with the rate below 2.5
pipe and three-way pipe need long distance
between length and width
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a$specification of the pipeline
Ground pipeline should first adopt the basic series, the ratio of the long side and the short side of the
direct pipeline should not be larger than 4:1. Pipeline should be outer diameter or outer border. Brick
and concrete pipeline should be inner diameter or inner border.
Pipeline diameter
Basic Accessorial Basic Accessorial Basic Accessorial
series series series series series series
100 80/90/100 300 300/320 900 850/900
120 110/120 360 340/360 1000 950/1000
140 130/140 400 380/400 1120 1060/1120
160 150/160 450 420/450 1250 1180/1250
180 170/180 500 480/500 1400 1320/1400
200 190/200 560 530/560 1600 1500/1600
220 210/220 630 600/630 1800 1700/1800
250 240/250 700 670/700 2000 1900/2000
280 260/280 800 750/800
(4) The thickness of the pipeline
The following table takes steel pipeline as an example, the other thickness of the pipeline material can be
looked up in the correlative standard of the book
Type Pipeline Square pipeline
diameter
Ground pipeline Middle and low High pressure
(long border )
pressure system system
dimension
80 320 0.5 0.5
340 450 0.6 0.6
0.8
480 630 0.8 0.6
670 1000 0.8 0.8
1120 1250 1.0 1.0 1.0
1320 2000 1.2 1.0 1.2
2500 4000 1.2 1.2 1.2
7.2 Pipeline Installation
(1) When the pipeline and its accessories pass through wall, board and roof, holes should be reserved in advance,
and the dimension and location should meet the design demand.
(2) The configure of the spot pipeline connection should not reduce its valid section.
(3) The hanger can t be set at the air-outlet, valve, examination-port and automatic control machine. And the
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suspender isn t suitable to be fixed at the flange.
(4) The configure of the spot pipeline connection should not reduce its valid section.
Horizontal installation Vertical installation
Bright Installation �d"3mm/m "d"20mm �d"2mm/m "d"20mm
Hidden Installation Right position, no obvious windage
� windage permeter " total windage
(5) The hanger of insulated pipeline should set outside the insulation layer and can t injure the insulation
layer.
(6) The distance between hangers:
Diameter (long border) Diameter (long border)
dimension< 400mm dimensione" 400mm
Horizontal distance d"4mm d"3mm
Vertical distance d"4mm�the part for fixing of every vertical pipeline
should not less than 2
7.3 Posit the air-outlet
(1) Type
Familiar outlet type: Louver outlet, disperser and linear outlet.
Linear outlet
(2) Specification
The specification of the air-outlet should be based on outer-diameter and outer-line.
`$ allowed windage of round air-outlet (mm)
diameter d"250 >250
allowed windage 0^�-2 0^�-3
a$ allowed windage of rectangle air-outlet (mm)
Diameter <300 300^�800 >800
allowed windage 0^�-1 0^�-2 0^�-3
Catercorner length <300 300^�500 >500
Two catercorner d"1 d"2 d"3
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(3) Posit the outlet
Air-outlet:
In the design and construction, no matter cooling and heating, cooling and heating are sent to places
through air-outlet, so it s important to select the right air-outlet.
Many factors limit the selection of air-outlet, for example:
`$ Indoor fitment
a$ Airflow in the room
b$ Installation and connection type of the air-outlet
The following issues should be noted:
`$ Try to assure the equality of the indoor parameters (especially the temperature)
a$ Prevent short-circuit of the air-inlet and air-outlet
b$ prevent bolding cold air directly to people in summer
Air-inlet:
`$The air-inlet shouldn t be set at places where people stays long to prevent short-circuit and
open-circuit. If adopting side-sending, it is suitable to set at the same side of the air-outlet.
a$For side air-inlet, normally, it is set under the same side. If adopting parallel air-sending, the air-inlet
also is set underside mostly. In order to avoid dust and filter, the height from the underline of the
air-inlet to the ground should at least keep 0.15m. For high big workshops, it is suitable to add air-inlet
or discharge air-let to discharge surplus-heat.
b$The distance from the air-inlet of the scatter setting to the wall should not less than half of the space
between scatter setting.
Fresh air-let:
`$ Fresh air-let should be set at clean places and far away from discharge air-let.
a$ Fresh air-let should be set upside the discharge air-let.
b$Fresh air-let should be set in the shade and avoid roof and west-wall. The distance from the ground is
at least 2m and 1m in case of green ground. And shutter is needed under the air-let.
(4) Facture and installation
`$Try to use the inlet panel of MIDEA brand.
a$Set a static-pressure box in the outlet to remove some noise
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b$Pay attention to the insulation of pipeline and the condensing water in the outlet.
c$The appearance of the air-outlet hasn t obvious impress, nick and spot. The color should be consistent and
welding points should be lubricous.
d$The match between inner sphere and outer sphere of sphericity air-outlet should rotate freely and isn t
flexible after orientation.
e$The diffusing loop and modulation loop of the scatter setting should be at the same axis and space
distributing in radial direction should be even.
8. Electric Installation
; Electric installation must be carried out according to National Standard.
; This chapter just for reference.
8.1 Brief Introduction
t$ All wire, part and material must conform to concerning national standards.
u$ All wiring work must be done by qualified person.
v$ Must ground well.
8.2 Power circuitry installation
t$ Sketch map of power wiring
u$ Selecting Creepage breaker
`$ The creepage protection switch is consist of creepage1�cbhV, zero-phase current mutual
inductance and automatic switch. It is applicable to AC 50Hz, single-phase, 220V or three-phase,
380V. It can prevent person from getting an electric shock and protect device from creepage. In
normal case, it can provide conversion for circuit.
a$ Selecting creepage breaker
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Selecting the creepage breaker according to 1.5-2 times of the sum of loading rated current.
v$ Selecting Manual Switch
When the power doesn t supply separately, selecting the manual switch and fuse capacity according to
the total capacity.
Total capacity (HP) Manual switch (A) Fuse (A)
10 14 100 75
15 18 100 100
19 28 150 150
29 36 200 200
37 47 300 250
48 50 300 300
w$ Selecting wiring specification
The following wiring specification just aim at Fluorin resinoid insulating wire, if use others, please
refer to the concerning national standard.
`$ Normal Fluorin resinoid insulating wire
Model Name
BV Fluorin resinoid insulating wire, copper-core
BLV Fluorin resinoid insulating wire, aluminum-core
BVR Fluorin resinoid insulating soft wire, copper-core
BVV Fluorin resinoid insulating wire, copper-core, round-type
BLVV Fluorin resinoid insulating wire, aluminum-core, round-type
BVVB Fluorin resinoid insulating wire, copper-core, flat-type
BLVVB Fluorin resinoid insulating wire, aluminum-core, flat-type
BV-105 Fluorin resinoid insulating wire, copper-core, heat-endurance 105!
RV Fluorin resinoid insulating connecting soft wire, copper-core
RVB Fluorin resinoid insulating connecting wire, copper-core, flat-type
RVS Fluorin resinoid insulating connecting wire, copper-core, twist-type
RVV Fluorin resinoid insulating connecting soft wire, copper-core, round-type
RVVB Fluorin resinoid insulating connecting soft wire, copper-core, flat-type
RV-105 Fluorin resinoid insulating connecting soft wire, copper-core, heat-endurance 105!
a$ Indoor power supply wiring
Indoor power supply
Power wiring
Power supply Manual switch Fuse
20m below 50m below
1-phase
15 A 2.5 mm2 6.0 mm2
220-240V^� 50Hz
b$ Outdoor power supply wiring
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MDV-D Installation
Sketch map of outdoor wiring
Outdoor power suply
Item Manual Creepage
Power supply Fuse Power wiring
Model switch protector
6.0 mm2or 6.0
380V^�3N^� 100mA 0.1sec mm2above
10HP 60A 50A
50Hz below (According to real
wiring distance)
Note: For 20HP and 30HP, wiring separately according to 10HP outdoor power wiring specification.
8.3 Control Wiring Connection Method
(1) Control Wiring Connection
`$ Correct Connection
a$ Typical Wiring Mistake
Part of Control wiring of Indoor units are connected at ring-type by mistake
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art of Control wiring of Indoor units are connected at star-type by mistake
Control wiring of all indoor units are connected at star-type by mistake
Polarity connection mistake for control wiring between outdoor/indoor units
Polarity connection mistake for control wiring between indoor units
u$ Specification of Control Wiring
Normal shield wires is as following:
Model Item
AVP Fluorin resinoid insulating shield wire, copper-core
AVP-105 Fluorin resinoid insulating shield wire, copper-core, heat-endurance 105!
RVP Fluorin resinoid insulating shield wire, copper-core
RVP-105 Fluorin resinoid insulating shield wire, copper-core, heat-endurance 105!
RVVP Fluorin resinoid insulating shield soft wire, copper-core
RVVP1 Fluorin resinoid insulating twist shield soft wire, copper-core
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MDV-D Installation
8.4 Wiring Diagram (Indoor/Outdoor)
t$ MDV-D100W/S(N2) MDV-D140W/S(N2) Wiring Diagram
(2) MDV-D280W/S(N2) Wiring Diagram
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(3) MDV-D560W/S(N2) Wiring Diagram
(4) MDV-D840W/S Wiring Diagram
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8.4 Wiring Diagram (Indoor/CCM)
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MDV-D Installation
8.5 Address Setting
t$ Address setting of outdoor units
The following table is applicable to communication address setting of main and auxiliary outdoor unit.
Address setting of outdoor unit
Main
20HP
Auxiliary
Main
30HP Auxiliary 1
Auxiliary 2
Note: SW3: Address setting switch for auxiliary outdoor unit
SW4: Address setting switch for main outdoor unit
u$ Address setting of indoor units
Address setting of indoor units Indoor unit ENC2
No. 1 0
No. 2 1
Indoor unit
No. 3 2
No.0 15
& & & &
No. 16 15
No. 17 0
No. 18 1
Indoor unit
No. 19 2
No.16 31
& & & &
No. 32 15
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(3) Network address setting(S1/S2)
It must set address before using NIM. Every air-conditioner in network has only one network address to
distinguish each other. Address code of air-conditioner in LAN is set by code switch on NIM, and the set range is
0-63.
Address Set Address Code
00 ~ 15
~
16 ~ 31
~
32 ~ 47
~
48 ~ 63
~
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