Gree GMV-140WL/A-T User manual

Owner's Manual
Air Conditioners
Models:
GMV-120WL/A-T
GMV-140WL/A-T
GMV-160WL/A-T
GMV-120WL/A-X
GMV-140WL/A-X
GMV-160WL/A-X
Thank you for choosing Air Conditioners, please read this owner’s manual carefully before
operation and retain it for future reference.If you have lost the Owner’s Manual, please contact
the local agent or visit www.gree.com or send email to [email protected] or electronic
version.
GREE reserves the right to interpret this manual which will be subject to any change due to
product improvement without further notice.
GREE Electric Appliances, Inc. of Zhuhai reserves the final right to interpret this manual.
DC Inverter Multi
VRF System User Manual
User Manual

Preface
Gree DC Inverter Multi VRF System, with the most advanced technologies in the world, uses eco-friendly
refrigerant R410A as its cooling medium. For correct installation and operation, please read this manual
carefully. Before reading the manual, please note that:
(1) EN 14511-2011。
Multi VRF system conforms to design standard: GB/T 18837-2002
(2) To ensure safety when operating this system, please strictly follow the instructions in this manual.
(3) The total capacity of running indoor units must not exceed that of the outdoor units. Otherwise, the
cooling (heating) effect of each IDU would be poor.
(4) Make sure that this manual is kept by direct operators and maintainers.
(5) In case of malfunction, please examine the following items and contact our authorized service
centers as soon as possible.
1)Nameplate (model, cooling capacity, product code, ex-factory date)
2)Malfunction status (detail description of conditions before and after malfunction occurs)
(6) All units have been strictly tested and proved to be qualified before ex-factory. To avoid damage or
operation failure which may be caused by improper disassembly, please do not disassemble units by yourself.
If disassembly is needed, please contact our authorized service centers.
(7) All graphics and information in this manual are only for reference. Manufacturer reserves the right for
changes in terms of sales or production at any time and without prior notice
(8) Under the standby status, the unit will consume a little power for ensuring reliability of complete unit,
maintaining normal communication and preheating refrigerant. When the unit won’t be used for a long time,
cut off the power of the complete unit. However, please preheat it when operating the unit next time.
Correct Disposal of this product
This marking indicates that this product should not be disposed with other household wastes
throughout the EU. To prevent possible harm to the environment or human health from uncontrolled
waste disposal, recycle it responsibly to promote the sustainable reuse of material resources. To return
your used device, please use the return and collection systems or contact the retailer where the
product was purchased. They can take this product for environmental safe recycling.
R410A(R32/125:50/50):2087.5

Contents
1 Safety Precautions............................................................................................................................................ 1
2 Product Introduction ........................................................................................................................................ 3
2.1 Names of Main Parts.........................................................................................................................................3
2.2 Combinations of Indoor and Outdoor Units ...................................................................................................3
2.3 Operating Range ...............................................................................................................................................4
3 Preparation before Installation ...................................................................................................................... 4
3.1 Standard Parts....................................................................................................................................................4
3.2 Installation Site...................................................................................................................................................4
3.3 Piping Work Requirements...............................................................................................................................5
4 Installation Instruction..................................................................................................................................... 6
4.1 Dimension of Outdoor Unit and Mounting Hole ............................................................................................6
4.2 Connection Pipe.................................................................................................................................................7
4.3 Installation of Connection Pipe......................................................................................................................11
4.4 Disassembly of Compressor Feet.................................................................................................................15
4.5 Vacuum Pumping, Refrigerant Adding..........................................................................................................16
4.6 Electric Wiring ..................................................................................................................................................17
5 Check Items after Installation and Test Operation...........................................................................................19
5.1 Check Items after Installation.........................................................................................................................19
5.2 Test operation and debugging .......................................................................................................................19
6 Common Malfunctions and Troubleshooting....................................................................................................23
7 Error Indication..........................................................................................................................................................25
8 Function Setting of Outdoor Unit .........................................................................................................................27
8.1 ODU Quiet Function........................................................................................................................................28
8.2 Cool & Heat Function......................................................................................................................................29
8.3 Forced Defrosting............................................................................................................................................30
8.4 Restore Factory Defaults................................................................................................................................30
8.5 Static Pressure Function.................................................................................................................................30
9 Maintenance and Care.............................................................................................................................................31
9.1 Outdoor Heat Exchanger................................................................................................................................31
9.2 Drain Pipe.........................................................................................................................................................31
9.3 Notice before Seasonal Use..........................................................................................................................31
9.4 Maintenance after Seasonal Use..................................................................................................................31
9.5 Parts Replacement..........................................................................................................................................31
10 After-sales Service .................................................................................................................................................31

DC Inverter Multi VRF System User Manual
1
1 Safety Precautions
Forbidden item! Improper operation might lead to personal injury or even death.
Item needs to be followed. Improper operation might lead to personal injury or property damage.
Please install the unit
according to instructions in
this manual. Read this
manual carefully before
starting up or checking the
machine.
Installation should be
performed by distributor or
qualified technicians. Do not
install the product by yourself.
Improper installation may
result in water leakage,
electric shock or fire hazard.
Before installation, please
check the power cord if it
complies with the power
supply requirement on the
nameplate. Make sure the
power supply is safe.
This air conditioner must be
properly grounded through
the receptacle to avoid
electric shock. The ground
wire shouldn’t be connected
with gas pipe, water pipe,
lightning arrester or telephone
line.
When installing, specialized
parts and accessories must
be used. Otherwise, it may
result in water leakage,
electric shock or fire hazard.
R410A refrigerant can
produce poisonous gas once
it meets fire, so please
ventilate the room
immediately if refrigerant
leaks out during installation.
Diameter of power cord must
be large enough. Damaged
power cord or connecting wire
must be replaced by
specialized electric cable.
After the power cord is
connected, please install the
cover of electric box to avoid
danger
Nitrogen must be charged
according to technical
requirements.
Short circuit is forbidden. Do
not cancel the pressure
switch, otherwise unit may be
damaged.
For units with wired
controllers, do not connect
power supply until the wired
controller is well installed.
Otherwise, the wired
controller cannot be used.
When installation is finished,
please check and make sure
the drain pipe, pipeline and
electric wire are all well
connected so as to avoid
water leakage, refrigerant
leakage, electric shock and
fire hazard.
Do not extend fingers or
objects into air outlet or return
air grille.
If you use gas heater or
petroleum heater in the same
room, please open the door or
window to maintain good air
circulation, otherwise the
room may be lack of oxygen.

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Never start or stop the air
conditioner by inserting or
removing the power cord.
Do not turn off the air
conditioner until it runs for at
least 5 minutes. Otherwise, oil
return of the compressor will
be affected.
Children are not allowed to
operate the air conditioner.
Do not operate the air
conditioner with wet hands.
Please turn off and unplug
your air conditioner before
cleaning. Otherwise, it may
cause electric shock or
personal injury.
Do not spray water on the air
conditioner or it will cause
malfunction or electric shock.
Do not expose the air
conditioner directly under
damp or corrosive
surroundings.
Connect power 8 hours before
operation. Do not disconnect
power when you want to stop
the unit in a short period of
time, e.g. in one night. (This is
for protecting the
compressor.)
Volatile liquid like thinner or
gasoline will damage the
appearance of air conditioner.
(Please use soft dry cloth and
wet cloth with mild detergent
to clean unit’s outer case.)
Under cool mode, do not set
the indoor temperature too
low. Keep the difference
between indoor temp and
outdoor temp within 5℃.
If abnormal condition occurs
(e.g. unpleasant smell),
please turn off the unit at once
and disconnect power supply.
Then contact Gree authorized
service center. If the air
conditioner continues to
operate despite of abnormal
condition, it may be damaged
and cause electric shock or
fire hazard.)
Do not repair the air
conditioner by yourself.
Improper repair will cause
electric shock or fire hazard.
Please contact Gree
authorized service center and
ask professional technicians
to repair it.
This appliance can be used by children aged from 8 years and above and persons with reduced physical,
sensory or mental capabilities or lack of experience and knowledge if they have been given supervision or
instruction
concerning use of the appliance in a safe way and understand the hazards involved. Children shall not play with
the appliance.
Cleaning and user maintenance shall not be made by children without supervision.
Gree Electric Appliances, Inc. of Zhuhai will not assume responsibility for any personal injury or property loss
caused by improper installation, improper debugging, unnecessary repair or not following the instructions of this
manual.

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2 Product Introduction
Gree Multi VRF System adopts inverter compressor technology. By changing the
displacement of compressor, stepless capacity regulation within range of 10%~100% can be
realized. Various product lineups are provided with capacity range from 8kW to 16kW, which can
be widely used in residential, commercial and working area and especially applicable to places
with big load change. Gree residential air conditioner is absolutely your best choice.
2.1 Names of Main Parts
Fig.1
No.
Name
Motor
Fan blade
Electric box
assembly
Gas pipe valve
Liquid pipe
valve
2.2 Combinations of Indoor and Outdoor Units
(1) See below the number of indoor units that can be connected to the outdoor unit.
(2) The total capacity of indoor units should be within 50%~135% of that of the outdoor unit.
Model
Min sets of connectable IDUs
Max sets of connectable ODUs
GMV-120WL/A-T
2
7
GMV-140WL/A-T
2
8
GMV-160WL/A-T
2
9
GMV-120WL/A-X
2
7
GMV-140WL/A-X
2
8
GMV-160WL/A-X
2
9
(3) can be connected to various indoor units. When any one of the indoor units receives
operating command, outdoor unit will start operation as per required capacity. When all
indoor units stop, outdoor unit will be shut off.

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2.3 Operating Range
Cooling
Outdoor temperature: -5℃～52℃
Heating
Indoor temperature: -20℃～27℃
3 Preparation before Installation
Note: Graphics here are only for reference. Please refer to actual products. Unspecified
dimensions are all in mm.
3.1 Standard Parts
Please use the supplied standard parts as required.
Parts for Outdoor Unit
No.
Name
Appearance
Qty
Remark
1
User Manual
1
2
Wiring (match with
resistance)
1
Must be connected to the
last IDU of communication
connection
3
Corrugated pipe
1
4
Chassis gluey plug
3
5
Drainage joint
1
3.2 Installation Site
Forbidden item! Improper operation might lead to personal injury or even death.
Item needs to be followed. Improper operation might lead to personal injury or property damage.
Select a location which is
strong enough to hold unit’s
weight so that unit can stand
still and erect.
Make sure the unit is not
exposed to sun and rain. And the
location can resist dust, typhoon
and earthquake.

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Please keep the unit away from
inflammable, explosive and
corrosive gas or waste gas.
Make sure the location has space
for heat exchange and
maintenance so that unit can
operate reliably with good
ventilation.
ODU and IDU should stay as
close as possible to shorten the
length of refrigerant pipe and
reduce bend angles.
Select a location which is out of
children’s reach. Keep the unit
away from children.
If the ODU is totally surrounded by walls, please refer to the following figures for space
dimension:
Fig.2
3.3 Piping Work Requirements
Refer to the table below for piping work requirements:
R410A Refrigerant System
Outer diameter (mm/inch)
Wall thickness(mm)
Φ6.35(1/4)
≥0.8
Φ9.52(3/8)
≥0.8
Φ12.70(1/2)
≥0.8
Φ15.9(5/8)
≥1.0
Φ19.05(3/4)
≥1.0

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4 Installation Instruction
Note: Graphics here are only for reference. Please refer to actual products. Unspecified
dimensions are all in mm.
4.1 Dimension of Outdoor Unit and Mounting Hole
Unit Outline and Installation Dimension（mm）
Fig.3 in mm
Model
A
B
C
D
E
GMV-120WL/A-T
GMV-140WL/A-T
GMV-160WL/A-T
GMV-120WL/A-X
GMV-140WL/A-X
GMV-160WL/A-X
900
340
1345
572
378

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4.2 Connection Pipe
4.2.1 Schematic Diagram of Piping Connection
Fig.4
4.2.2 Allowable Length and Height Difference of Connection Pipe
Y type branch joint is adopted to connect indoor and outdoor units. Connecting method is
shown in the figure below:
Note：Equivalent length of one Y-type branch is 0.5m.

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Fig.5 Allowable Length and Height Difference of Connection Pipe
Piping parameters of GMV-120WL/A-T，GMV-140WL/A-T，GMV-160WL/A-T，
GMV-120WL/A-X，GMV-140WL/A-X and GMV-160WL/A-X::
Allowable
value
Fitting pipe
Total length (actual length) of fitting pipe
300m
L1+L2+L3+a+b++c+d
Length of farthest fitting pipe (m)
Actual length
120m
L1+L2+L3+d
Equivalent length
150m
From the 1st branch to the farthest indoor pipe
40m
L2+L3+d
Height difference between ODU
and IDU
ODU at upper side
50m
——
ODU at lower side
40m
——
Height difference between IDUs
15m
——
4.2.3 Dimension of Pipe (Main Pipe) from ODU to the 1st Indoor Branch
Dimension of pipe from ODU to the 1st indoor branch will be determined by the dimension of
outdoor connection pipe.

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Fig.6
Dimension of outdoor connection pipe
Basic module
Pipe dimension
Connection method
Gas pipe (mm)
Liquid pipe（mm）
GMV-120WL/A-T
φ15.9
φ9.52
GMV-140WL/A-T
φ15.9
φ9.52
GMV-160WL/A-T
φ19.05
φ9.52
GMV-120WL/A-X
φ15.9
φ9.52
GMV-140WL/A-X
φ15.9
φ9.52
GMV-160WL/A-X
φ19.05
φ9.52
4.2.4 Selection of Indoor Branches
Select indoor branches according to the total capacity of downstream indoor units. If the
capacity exceeds that of the outdoor unit, capacity of outdoor unit prevails.
Fig.7

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R410A Refrigerant system
Total capacity of downstream indoor units X (kW)
Model
Y type branch
X＜20
FQ01A
20≤X≤30
FQ01B
30＜X≤70
FQ02
70＜X≤135
FQ03
135＜X
FQ04
4.2.5 Dimension of Pipe between Indoor Branches
Select pipe between indoor branches according to the capacity of downstream indoor units; If
the capacity exceeds that of the outdoor unit, capacity of outdoor unit prevails.
Fig.8
Total capacity of downstream indoor units C (kW)
Gas pipe（mm）
Liquid pipe（mm）
C ≤5.6
Φ12.7
Φ6.35
5.6＜C≤14.2
Φ15.9
Φ9.52
14.2＜C≤22.4
Φ19.05
Φ9.52

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4.2.6 Dimension of Pipe between Indoor Branch and IDU
Dimension of pipe between indoor branch and IDU should be consistent with the dimension of
indoor pipe.
Fig. 9
Rated capacity of IDU C(kW)
Gas pipe (mm)
Liquid pipe (mm)
C≤2.8
Φ9.52
Φ6.35
2.8＜C≤5.0
Φ12.7
Φ6.35
5.0＜C≤14.0
Φ15.9
Φ9.52
14.0＜C≤16.0
Φ19.05
Φ9.52
16.0＜C≤28.0
Φ22.2
Φ9.52
Note: If the distance between IDU and its nearest branch is over 10m, then the liquid
pipe of IDU (rated capacity ≤5.0kW) shall be enlarged.
4.3 Installation of Connection Pipe
4.3.1 Precautions for the Installation of Connection Pipe
(1)
Conform to the following principles during pipe connection: Connection pipe should be as
short as possible, so is the height difference between indoor and outdoor units. Keep the
number of bends as little as possible. Radius of curvature should be as large as possible.
(2) Weld the connection pipe between indoor and outdoor units. Please strictly follow the
requirements for welding process. Rosin joint or pin hole is not allowed.
(3) Radius of bending parts should be over 200mm. Note that pipes cannot be repeatedly

DC Inverter Multi VRF System User Manual
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bent or stretched; otherwise the material will get harder. Do not bend or stretch the pipe
for more than 3 times at the same position.
4.3.2 Flaring Process
(1) Use pipe cutter to cut the connection pipe in case it is unshaped.
(2) Keep the pipe downward in case cutting scraps get into the pipe. Clear away the burrs
after cutting.
(3) Remove the flared nut connecting indoor connection pipe and outdoor unit. Then use
flaring tool to fix the flared nut into the pipe (as shown in Fig.10).
(4) Check if the flared part is flaring evenly and if there is any crack.
Fig. 10
4.3.3 Pipe Bending
(1) Reshape the pipe by hand. Be careful not to damage the pipe.
Fig. 11 Fig. 12
(2) Do not bend the pipe over 90°.
(3) If pipe is repeatedly bent or stretched, it will get hard and difficult to bend and stretch again.
Therefore, do not bend or stretch the bend for over 3 times.
(4) In case that direct bending will open cracks to the pipe, first use sharp cutter to cut the
insulating layer, as shown in Fig.12. Do not bend the pipe until it is exposed. When bending is
done, wrap the pipe with insulating layer and then secure it with adhesive tape.
4.3.4 Indoor Pipe Connection
(1) Remove pipe cover and pipe plug.
(2) Direct the flared part of copper pipe to the center of screwed joint. Twist on the flared nut
tightly by hand, as in Fig.13. (Make sure indoor pipe is correctly connected. Improper location
of the center will prevent flared nut from being securely twisted. Thread of nut will get
damaged if the flared nut is twisted forcibly.)
(3) Use torque wrench to twist on the flared nut tightly until the wrench gives out a click sound.
(Hold the handle of wrench and make it at right angle to the pipe. as in Fig.14)
(4) Use sponge to wrap the un-insulated connection pipe and joint. Then tie the sponge tightly

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with plastic tape.
(5) Connection pipe should be supported by a bearer rather than the unit.
(6) The bending angle of piping should not be too small; otherwise the piping might have cracks.
Please use a pipe bender to bend the pipe.
(7) When connecting IDU with connection pipe, do not pull the big and small joints of IDU with
force in case the capillary tube or other tubes have cracks and cause leakage.
Fig. 13 Fig. 14
4.3.5 Outdoor Pipe Connection
Twist the flared nut on the connection pipe of outdoor valves. Twisting method is the same as
for indoor pipe connection.
Below is the piping diagram of GMV-120WL/A-T,GMV-140WL/A-T ,GMV-160WL/A-T,
GMV-120WL/A-X,GMV-140WL/A-X and GMV-160WL/A-X. According to customer requirement or
space limit, outlet pipe can be installed from the front, right or rear side.
Fig.15

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4.3.6 Installation of Y-type Branch
(1) Y-type Branch
Fig.16
(2) Y-type branch has several pipe sections with different dimension, which facilitates to match
with various copper pipes. Use pipe cutter to cut in the middle of the pipe section that is of
proper dimension and remove burrs as well. See Fig.17.
(3) Y-type branch must be installed vertically or horizontally.
Fig.17
(4) Branch shall be isolated by insulating material that can bear 120°or even higher
temperature. The attached foam of branch cannot be taken as insulating material.
4.3.7 Thermal Insulation for Pipeline
(1) For multi VRF system, every copper pipe should be labeled so as to avoid misconnection.
(2) At the branch inlet, leave at least 500mm straight pipe section.
(3) Thermal insulation for pipeline
1) To avoid condensate or water leakage on the connection pipe, the gas pipe and liquid pipe
must be wrapped with thermal insulating material and adhesive tape for insulation from the
air.
2) Thermal insulating material shall be able bear the pipe temperature. For heat pump unit,
liquid pipe should bear 70℃or above and gas pipe should bear 120℃or above. For cooling
only unit, both liquid pipe and gas pipe should bear 70℃or above.
Example: Polyethylene foam (bear 120℃or above); foaming polyethylene (bear 100℃or
above)
3) Joints of indoor and outdoor unit should be wrapped with insulating material and leave no
gap between pipe and wall. See Fig.18.

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Fig.18
4) Thermal insulating material of branches should be the same as that of the pipeline. The
attached foam of branches cannot be taken as insulating material.
5) When wrapping the tape, the later circle should cover half of the former one. Don’t wrap the
rape too tight, otherwise the insulation effect will be weakened.
6) After wrapping the pipe, apply sealing material to completely seal the hole on the wall.
4.3.8 Support and Protection of Pipeline
(1) Support should be made for hanging connection pipe. Distance between each support
cannot be over 1m.
(2) Protection against accidental damage should be made for outdoor pipeline. When pipeline
exceeds 1m, a pinch board should be added for protection.
4.4 Disassembly of Compressor Feet
In order to prevent unit from damage during transportation, 2 metal pieces are fitted to
outdoor unit’s compressor feet before unit leaves factory. See fig.19.
Fig.19
When installing the unit, metal pieces for transportation must be removed. Then fasten the
binding nuts again and wrap back soundproofing cotton.
Note: If unit runs with metal pieces fitting on, compressor will shake abnormally and
unit’s operating life will be shortened.

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4.5 Vacuum Pumping, Refrigerant Adding
4.5.1 Vacuum Pumping
(1) Outdoor unit has been charged with refrigerant before delivery. Field-installed connection
pipe needs to be charged with additional refrigerant.
(2) Confirm whether outdoor liquid and gas valves are closed.
(3) Use vacuum pump to withdraw the air inside indoor unit and connection pipe from the
outdoor valve, as shown below.
Fig. 20
4.5.2 Refrigerant Adding
(1) Refrigerant quantity of outdoor unit before delivery:
Model
GMV-120WL/A-
T
GMV-140WL/A-
T
GMV-160WL/A-
T
GMV-120WL/A-
X
GMV-140WL/A-
X
GMV-160WL/A-
X
Refrigeran
t Qty (kg)
5.0
5.0
5.0
5.0
5.0
5.0
Note:
①The refrigerant amount charged before delivery doesn’t include the amount that needs to be
added to indoor units and the connection pipeline.
②Length of connection pipe is decided on site. Therefore the amount of additional refrigerant
shall be decided on site according to the dimension and length of field-installed liquid pipe.
③Record the amount of additional refrigerant for convenience of after-sales service.
(2) Calculation of the amount of additional refrigerant
Calculation method of the quantity of additional refrigerant (based on liquid pipe)
Quantity of additional refrigerant = ∑length of liquid pipe X quantity of additional refrigerant per
meter
Quantity of additional refrigerant per meter for liquid pipe（kg/m）
Φ22.2
Φ19.05
Φ15.9
Φ12.7
Φ9.52
Φ6.35
0.35
0.25
0.17
0.11
0.054
0.022
Note: Liquid pipe that is within 20m doesn’t need to be added with refrigerant.
First confirm that there is no leakage from the system. When compressor is not working,
charge additional R410a with specific amount to the unit through the filling opening of the liquid
pipe valve of the outdoor unit. If required amount cannot be quickly filled due to pressure increase

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of the pipe, then set the unit in cooling startup and fill refrigerant from the low pressure check valve
of the outdoor unit.
(3) Calculation example
Fig. 21
IDU
No.
IDU ①
IDU ②
IDU ③
IDU ④
Model
Duct type
GMV-ND72PL/B-T
Duct type
GMV-ND50PL/B-T
Duct type
GMV-ND36PL/B-T
Duct type
GMV-ND25PL/B-T
Liquid pipe:
No.
A
B
C
D
Pipe size
φ9.52
φ9.52
φ9.52
φ6.35
Length
10m
5m
5m
5m
No.
a
b
c
d
Pipe size
φ9.52
φ6.35
φ6.35
φ6.35
Length
3m
3m
2m
1m
Total length of each liquid pipe
φ9.52：A+B+C+a=10+105+5+3=23m
φ6.35: D+b+c+d=5+3+2+1=11m
Note: Liquid pipe that is within 20m doesn’t need to be added with refrigerant.
Therefore, the minimum quantity of additional refrigerant = (23-20)×0.054+11×0.022＝0.404kg
4.6 Electric Wiring
4.6.1 Notices for Wiring
☆Install units according to national wiring codes.
☆Use air conditioner specialized power supply and make sure that it is consistent with
system’s rated voltage.
☆Do not pull the power cord with force.
☆All electrical installation must be performed by qualified technicians in accordance with local
laws, regulations and this user manual.
☆Caliber of the power cord must be large enough. A damaged power cord or connection wire
must be replaced by specialized electrical cords.
☆If the supply cord is damaged, it must be replaced by the manufacturer or its service agent
or a similarly qualified person in order to avoid a hazard;
☆A circuit breaker having a contact separation of at least 3mm in all poles should be fixed in