Gree GRS-Cm18PdRe/NhA-M User manual

Owner's Manual
Original Instructions
Air-to-water Heat Pump
Model：
GRS-Cm18PdRe/NhA-M

To Users
Thank you for selecting Gree’s product. Please read this instruction manual carefully before installing
and using the product, so as to master and correctly use the product. In order to guide you to correctly
install and use our product and achieve expected operating effect, we hereby instruct as below:
(1) This equipment should be installed, operated or maintained by the qualified servicemen who
have had specific training. During operation, all safety issues covered in the labels, User’s
Manual and other literature should be followed strictly. This equipment is not intended for use by
persons (including children) with reduced physical, sensory or mental capabilities, or lack of
experience and knowledge, unless they have been given supervision or instruction concerning
use of the appliance by a person responsibility for their safety. Children should be supervised to
ensure that they do not play with the appliance.
(2) This product has gone through strict inspection and operational test before leaving the factory. In
order to avoid damage due to improper disassembly and inspection, which may impact the
normal operation of unit, please do not disassemble the unit by yourself. You can contact with
the special maintenance center of our company if necessary.
(3) For personal injury or property loss and damage caused by improper operation such as
improper installation and debugging, unnecessary maintenance, violation of related national
laws and rules and industrial standard, and violation of this instruction manual, etc., we will bear
no liability.
(4) When the product is faulted and cannot be operated, please contact with our maintenance
center as soon as possible by providing the following information.
•Contents of nameplate of product (model, cooling/heating capacity, product No., ex-factory
date).
•Malfunction status(specify the situations before and after the error occurs).
(5) All the illustrations and information in the instruction manual are only for reference. In order to
make the product better, we will continuously conduct improvement and innovation. We have
the right to make necessary revision to the product from time to time due to the reason of sales
or production, and reserve the right to revise the contents without further notice.
(6) The final right to interpret for this instruction manual belongs to Gree Electric Appliances Inc. of
Zhuhai.

Contents
1 Safety Notices (Please be sure to abide)......................................................................1
2 Diagram of the Operating Principle...............................................................................8
3 Operating Principle of the Unit ......................................................................................9
4 Nomenclature................................................................................................................10
5 Installation Example .....................................................................................................10
6 Appearance ...................................................................................................................11
7 Installation Guideline of Monobloc Unit .....................................................................12
7.1 Instruction to installation ......................................................................................................12
7.2 Installation of monobloc unit ................................................................................................12
8 Optional Electric Heater ...............................................................................................15
9 Charging and Discharging of Refrigerant...................................................................15
10 Installation of Insulated Water Tank ..........................................................................17
10.1 Selection of Water Pipe ..................................................................................................... 17
10.2 Model Selection of Water Pump......................................................................................... 18
10.3 Installation measure...........................................................................................................19
10.4 Connection of waterway system ........................................................................................ 20
10.5 Requirements on water quality........................................................................................... 21
10.6 Electric wiring work ............................................................................................................21
11 Wring Diagram.............................................................................................................22
11.1 Control Board..................................................................................................................... 22
11.2 Electric Wiring.................................................................................................................... 23
12 Commissioning...........................................................................................................24
12.1 Check before startup ......................................................................................................... 24
12.2 Test run..............................................................................................................................25
13 Daily Operation and Maintenance .............................................................................26
13.1 Recovery ...........................................................................................................................27
13.2 Decommissioning ..............................................................................................................28
13.3 Notice before Seasonal Use ..............................................................................................29

Air-to-water Heat Pump
1
1 Safety Notices (Please be sure to abide)
WARNING: If not abide strictly, it may cause severe damage to the unit or the people.
NOTE: If not abide strictly, it may cause slight or medium damage to the unit or the people.
This sign indicates that the operation must be prohibited. Improper operation may cause severe
damage or death to people.
This sign indicates that the items must be observed. Improper operation may cause damage to
people or property.
NOTE
After receipt of the unit, check it for appearance, unit model compared with your desire and
attachments.
Design and installation work of the unit must be performed by authorized personnel according to
applicable laws and regulations and this Instruction.
After installation work, the unit cannot be energized unless there is not any problem in check.
Ensure periodical clean and maintenance of the unit after normal operation of the unit for longer life
and reliable operation.
If the supply cord is damaged, it must be replaced by the manufacturer, its service agent or similarly
qualified persons in order to avoid a hazard.
The appliance shall be installed in accordance with national wiring regulations.
This product is a kind of comfort air conditioning, and is not allowed to be installed where there are
corrosive, explosive and inflammable substances or smog; otherwise it would lead to operation failure,
shortened service life, five hazard or even severe injuries. Special air conditions are required for where
mentioned above.
Correct Disposure
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.
R32:675

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WARNING
Once abnormality likeburning
smell occurs, please cut off the
power supply immediately and
then contact with service
center.
If the abnormality still exists,
the unit may be damaged and
electric shock or fire may
result.
Don't operate the unit with wet
hand.
Otherwise, it may cause electric
shock.
Before installation, please see
if the voltage of local place
accords with that on
nameplate of unit and capacity
of power supply, power cord or
socket is suitable for input
power of this unit.
Special circuit must be
adopted for power supply to
prevent fire.
Do not use octopus
multipurpose plug or mobile
terminal board for wire
connection.
Be sure to pull out the power
plug and drain the
unit and water tank when unit
is not in use for a long time.
Otherwise, the accumulated dust
may cause overheating,
fire or
freeze of water tank or heater
exchanger in winter.
Never damage the electric
wire or use the one which is
not specified.
Otherwise, it may cause
overheating or fire.
Before cleaning please cut off
the power supply.
Otherwise, it may cause
electric shock or damage.
The power supply must adopt
special circuit with leakage
switch and enough capacity.
User cannot change power
cord socket without prior
consent.
Wiring working must be done
by professionals. Ensure good
earthing and don't change
earthing mode of unit.

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WARNING
Earthing: the unit must be
earthed reliably! The earthing
wire should
connect with
special device of buildings.
If not, please ask the qualified
personnel to install.
Furthermore, don't connect
earth wire to gas pipe, water
pipe, drainage pipe or any
other improper places which
professional does not
recognize.
Never insert any foreign
matter into outdoor unit to
avoid damage. And never
insert your hands into the air
outlet of outdoor unit.
Don't attempt to repair the unit
by yourself.
Improper repair may cause
electric shock or fire, so you
should contact the service
center to repair.
Don't step on the top of the unit
or place anything on it.
There is the danger of fall of
things or people.
Never block the air inlet and
outlet of unit.
It may reduce efficiency or
cause stop of the unit and
even fire.
Keep pressurized spray, gas
holder and so on away from
the unit above 1m.
It may cause fire or explosion.
Please note whether the
installation stand is firm
enough or not.
If damaged, it may cause fall of
the unit and injury of people.
Unit should be installed at the
place with good ventilation to
save energy.
When there is not water in
water tank, never power the
unit on to run.

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WARNING
Do not use means to accelerate the defrosting process or to clean, other than those
recommended by the manufacturer. Should repair be necessary, contact your nearest authorized
service center. Any repairs carried out by unqualified personnel may be dangerous. The appliance shall
be stored in a room without continuous operating ignition sources. (For example: open flames, an
operating gas appliance or an operating electric heater.) Do not pierce or burn.
Appliance shall be installed, operated and stored in a room with a floor area larger than
Xm.(Please refer to table “a” in section of “ Safety Operation of Inflammable Refrigerant” for space X.)
Appliance filled with flammable gas R32. For repairs, strictly follow manufacturer’s instructions
only. Be aware that refrigerants not contain odor. Read specialist’s manual.
If a stationary appliance is not fitted with a supply cord and a plug, or with other means for
disconnection from the supply mains having a contact separation in all poles that provides full
disconnection under overvoltage category III conditions, the instructions shall state that means for
disconnection must be incorporated in the fixed wiring in accordance with the wiring rules.
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.
The appliance shall be stored in a well-ventilated area where the room size corresponds to the
room area as specified for operation.
The appliance shall be stored in a room without continuously operating open flames (for example
an operating gas appliance) and ignition sources (for example an operating electric heater).
The appliance shall be stored so as to prevent mechanical damage from occurring.
NOTE
Appliance filled with flammable gas R32.
Before use the appliance, read the owner’s manual first.
Before install the appliance, read the installation manual first.
Before repair the appliance, read the service manual first.
To realize the function of the air conditioner unit, a special refrigerant circulates in the system. The
used refrigerant is the fluoride R32, which is specially cleaned. The refrigerant is fla
mmable and
inodorous. Furthermore, it can leads to explosion under certain conditions. But the flammability of the
refrigerant is very low. It can be ignited only by fire.
Compared to common refrigerants, R32 is a nonpolluting refrigerant with no harm to the

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NOTE
ozonosphere. The influence upon the greenhouse effect is also lower. R32 has got very good
thermodynamic features which lead to a really high energy efficiency. The units therefore need a less
filling.
Before installation, please check if the adopted power is accordance with that listed on nameplate,
and check the safety of power.
The unit shall contact with the supply mains by a full disconnection device under overvoltage
category Ⅲ.
Before using, please check and confirm if wires and water pipes are connected correctly to avoid
water leakage, electric shock or fire etc.
Don’t operate the unit with wet hand, and don’t allow children to operate the unit.
The On/off in the instruction is for the operation to on and off button of PCB for users; cut off power
means to stop supplying power to the unit.
Don’t directly expose the unit under the corrosive ambient with water or dampness.
Don’t operate the unit without water in water tank. The air outlet/inlet of unit cannot be blocked by
other objects.
The water in unit and pipeline should be discharged if the unit is not in use, to prevent the water
tank, pipe line and water pump from frost-cracking.
Never press the button with sharp objects to protect manual controller. Never use other wires
instead of special communication line of the unit to protect control elements. Never clean the manual
controller with benzene, thinner or chemical cloth to avoid fading of surface and failure of elements.
Clean the unit with the cloth soaked in neutral eradicator. Slightly c
lean the display screen and
connecting parts to avoid fading.
The power cord must be separated with the communication line.
Any person who is involved with working on or breaking into a refrigerant circuit should hold a
current valid certificate from an industry-
accredited assessment authority, which authorizes their
competence to handle refrigerants safely in accordance with an industry recognized assessment
specification.
Servicing shall only be performed as recommended by the equipment manufacturer. Maintenance
and repair requiring the assistance of other skilled personnel shall be carried out under the supervision
of the person competent in the use of flammable refrigerants.
Maximum and minimum water operating temperatures
Item Minimum water operating temperatures Maximum water operating
temperatures
Cooling 5°C 25°C
Heating 25°C 60°C
Hot water 30°C 55°C

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Maximum and minimum water operating pressures
Item Minimum water operating pressures Maximum water operating
pressures
Cooling
0.05MPa 0.25MPa
Heating
Hot water
Maximum and minimum entering water pressures.
Item Minimum entering water pressures Maximum entering water
pressures
Cooling
0.05MPa 0.25MPa
Heating
Hot water
The range of external static pressures at which the appliance was tested (add-on heat pumps, and
appliances with supplementary heaters, only); If the supply cord is damaged, it must be replaced by
the manufacturer, its service agent or similarly qualified persons in order to avoid a hazard.
The appliance is intended to be permanently connected to the water mains and not connected by a
hose-set.
If there is any question, please contact with local dealer, authorized service center, agencies or our
company directly.
NOTE
If any hot work is to be conducted on the refrigeration equipment or any associated parts,
appropriate fire extinguishing equipment shall be available to hand. Have a dry powder or CO2fire
extinguisher adjacent to the charging area.
Where electrical components are being changed, they shall be fit for the purpose and to the correct
specification. At all times the manufacturer’s maintenance and service guidelines shall be followed. If
in doubt consult the manufacturer’s technical department for assistance.
The following checks shall be applied to installations using flammable refrigerants:
The charge size is in accordance with the room size within which the refrigerant containing parts are
installed;
The ventilation machinery and outlets are operating adequately and are not obstructed;
If an indirect refrigerating circuit is being used, the secondary circuit shall be checked for the
presence of refrigerant;
Marking to the equipment continues to be visible and legible. Markings and signs that are illegible
shall be corrected;
Refrigeration pipe or components are installed in a position where they are unlikely to be exposed to
any substance which may corrode refrigerant containing components, unless the components are
constructed of m
aterials which are inherently resistant to being corroded or are suitably protected
against being so corroded.
Repair and maintenance to electrical components shall include initial safety checks and component

Air-to-water Heat Pump
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NOTE
inspection procedures. If a fault exists that could compromise safety, then no electrical supply shall be
connected to the circuit until it is satisfactorily dealt with. If the fault cannot be corrected immediately but
it is necessary to continue operation, an adequate temporary solution shall be used.
This shall be
reported to the owner of the equipment so all parties are advised.
I
nitial safety checks shall include: that capacitors are discharged: this shall be done in a safe
manner to avoid possibility of sparking; that no live electrical components and wiring are exposed while
charging, recovering or purging the system; that there is continuity of earth bonding.
During repairs to sealed components, all electrical supplies shall be disconnected from the
equipment being worked upon prior to any removal of sealed covers, etc. If it is absolutely necessary to
have an electrical supply to equipment during servicing, then a permanently operating form of leak
detection shall be located at the most critical point to warn of a potentially hazardous situation.
Particular attention shall be paid to the following to ensure that by working on electrical components,
the casing is not altered in such a way that the level of protection is affected. This shall include damage
to cables, excessive number of connections, terminals not made to original specification, damage to
seals, incorrect fitting of glands, etc.
Ensure that apparatus is mounted securely.
Ensure that seals or sealing materials have not degraded such that they no longer serve the
purpose of preventing the ingress of flammable atmospheres. Replacement parts shall be in accordance
with the manufacturer’s specifications.
NOTE: The use of silicon sealant may inhibit the effectiveness of some types of leak detection
equipment.
Intrinsically safe components do not have to be isolated prior to working on them.
Do not apply any permanent inductive or capacitance loads to the circuit without ensuring that this
will not exceed the permissible voltage and current permitted for the equipment in use.
Intrinsically safe components are the only types that can be worked on while live in the presence of
a flammable atmosphere. The test apparatus shall be at the correct rating.
Replace components only with parts specified by the manufacturer. Other parts may result in the
ignition of refrigerant in the atmosphere from a leak.
Check that cabling will not be subject to wear, corrosion, excessive pressure, vibration, sharp edges
or any other adverse environmental effects. The check shall also take into account the effects of ageing
or continual vibration from sources such as compressors or fans.
Under no circumstances shall potential sources of ignition be used in the searching for or detection
of refrigerant leaks. A halide torch (or any other detector using a naked flame) shall not be used.
Equipment shall be labeled stating that it has been de-commissioned and emptied of refrigerant.
The label shall be dated and signed. Ensure that there are labels on the equipment stating the
equipment contains flammable refrigerant.

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2 Diagram of the Operating Principle
NOTE: In actual engineering, terminals heating/cooling device are selected by the user.

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3 Operating Principle of the Unit
The DC inverter air source heat pump system comprises the ODU, water tank, and user terminals.
Operation functions:
(1) Hot water;
(2) Heating;
(3) Cooling;
(4) Hot water+ Heating;
(5) Heating+ water heating;
(6) Mute function;
Hot water：In hot water mode, through heat pump circulation, the unit absorbs heat from the
low-grade energy (low-temperature air) in the surrounding environment and exchanges the heat with
water through the water-side heat exchanger. By controlling the engineering water valve, the water in the
engineering water tank enters the water-side heat exchanger to absorb heat. It is heated circularly to
reach the set value of water tank temperature and meet the user’s hot water demand. Hot water mode
includes: standard hot water, energy-saving hot water and fast hot water.
Heating：In heating mode, through heat pump circulation, the unit absorbs heat from the low-grade
energy (low-temperature air) in the surrounding environment and exchanges the heat with water through
the water-side heat exchanger. By controlling the engineering water valve, the water in user terminals
enters the water-side heat exchanger to absorb heat. It is heated circularly to reach the set value of
leaving water temperature and meet the user’s heating demand.
Cooling：In cooling mode, through refrigeration circulation, the unit absorbs heat from the cool
water in the water-side heat exchanger and releases the heat to the low-grade energy (high-temperature
heat source) in the surrounding environment. By controlling the engineering water valve, the water in
user terminals enters the water-side heat exchanger to release heat. It is cooled circularly to reach the
set value of leaving water temperature and meet the user’s cooling demand.
Hot water+ Heating：In the mode of hot water + heating, hot water mode is given priority. In other
words, the unit will not switch to heating mode until the water tank temperature reaches the set value.
When in heating mode, if the water tank temperature is not satisfied, the unit will immediately switch to
hot water mode.
Hot water+ Cooling：In the mode of hot water + cooling, hot water mode is given priority. In other
words, the unit will not switch to cooling mode until the water tank temperature reaches the set value.
When in cooling mode, if the water tank temperature is not satisfied, the unit will immediately switch to
hot water mode.
Mute function：When mute function is enabled, the unit will automatically control and lower its
operating noise. This function is available in all kinds of running modes.

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4 Nomenclature
GRS - / -
1
2
3
4
5
6
7
8
9
10
11
SN
Description
Options
1
Product code
GRS—Heat pump water heater
2 Heating method
D—Direct heating; C—Circulating heating; S—Static heating;
Dm-Direct heating modular;
Cm- Circulating modular
3
Functions
Q—Multifunctional; Null for single function
4
Heating capacity code
Nominal heating capacity(Unit:kW)
5
Inverter system
Pd—DC inverter; Null for fixed speed
6
type of heat pump
Re—Low-temperature heat pump; Null for Normal-temperature heat pump
7
Water tank mode
E—100L;F—150L;G—200L;H—250L;Null in case of no water tank
8
Climate condition
Null for T1;T2-Low temp;T3-High temp
9
Refrigerant
R22—Default;R407c—N;R410A—Na;R134a—Nb;R32—Nh;R417A—Ne
10
Design number
A,B,C…or A1,A2…,B1,B2…
11
Power supply
Refer to QJ/GD23.00.004
Model Line-Up
Model Name
Capacity
Power supply
Heating1, kW
Heating2, kW
GRS-Cm18PdRe/NhA-M 18.1 16.1 380-415V 3N~ 50Hz
NOTES:
(1) 1Capacities and power inputs are based on the following conditions:
Indoor Water Temperature 30°C/35°C, Outdoor Air Temperature 7°C DB/6°C WB
(2) 2Capacities and power inputs are based on the following conditions:
Indoor Water Temperature 23°C/18°C, Outdoor Air Temperature 35°C DB/24°C WB
Operation Range
Mode Heat Source Side Temperature (°C) User Side Temperature (°C)
Hot water
-30~45
30~55
Heating
-30~35
25~60
Cooling
-10~48
5~25
5 Installation Example
CASE 1: Connecting Under-floor Coil for Heating and Cooling
NOTES:
(1) In this diagram, under-floor coil represents the user’s heating/cooling terminal. In actual
engineering, terminals are selected by the user.
(2) By pass valve must be installed to secure enough water flow rate, and by pass valve should be
installed at the collector.

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CASE 2: Connecting Sanitary Water Tank and Under-floor Coil
Under-floor coil
NOTES:
(1) In this diagram, under-floor coil represents the user’s heating/cooling terminal. In actual
engineering, terminals are selected by the user.
(2) In this case, three-way valve should be installed and should be complied with installation of this
manual.
WARNING
The 3-way valve should select under floor loop when electric power is supplied to wire (ON)
and wire (N).
The 3-way valve should select water tank loop when electric power is supplied to wire (OFF)
and wire (N).
(ON): Live signal (Heating/Cooling system) from the main board to the 3-way valve.
(OFF): Live signal (Water tank loop) from the main board to the 3-way valve.
(N): Neutral signal from the main board to the 3-way valve.
6 Appearance
GRS-Cm18PdRe/NhA-M

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7 Installation Guideline of Monobloc Unit
7.1 Instruction to installation
(1) Installation of the unit must be in accordance with national and local safety codes.
(2) Installation quality will directly affect the normal use of the air conditioner unit. The user is
prohibited from installation. Please contact your dealer after buying this machine. Professional
installation workers will provide installation and test services according to installation manual.
(3) Do not connect to power until all installation work is completed.
(4) The foot brackets of the compressor is used to reduce vibration during transport. Before
commissioning, they must be removed, otherwise it would lead to unnecessary faults. When
foot brackets have been removed, the fastening screws must be tightened so as to prevent the
compressor from jumping out during operation.
7.2 Installation of monobloc unit
7.2.1 Selection of installation location of monobloc unit
(1) Monobloc unit must be installed on a firm and solid support.
(2) Avoid placing the monobloc unit under window or between two constructions, hence to prevent
normal operating noise from entering the room.
(3) Air flow at inlet and outlet shall not be blocked.
(4) Install at a well-ventilated place, so that the machine can absorb and discharge sufficient air.
(5) Do not install at a place where flammable or explosive goods exist or a place subject to severe
dust, salty fog and polluted air.
7.2.2 Outline dimension of monobloc unit
GRS-Cm18PdRe/NhA-M
Unit: mm

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7.2.3 Space requirements for installation
Unit: mm
NOTE: In confederation of space restriction, for the left-handed figure, except the outlet side, distance
between the unit and the nearest barrier at other three sides are allowed to be no less than 500mm; for
the right-handed figure, distance between the inlet side and the nearest barrier is allowed to be no less
than 500mm.
7.2.4 Precautions on installation of monobloc unit
(1) When moving outdoor unit, it is necessary to adopt 2 pieces of long enough rope to hand the
unit from 4 directions. Included angle between the rope when hanging and moving must be 40°
below to prevent center of the unit from moving.
(2) Adopt bolts components to tighten feet and under frame when installing.
(3) Monobloc unit should be installed on concrete base that is 10cm height.
(4) Requirements on installation space dimension of unit’s bodies are shown in following drawing.
(5) Monobloc unit must be lifted by using designated lifting hole. Take care to protect the unit
during lift. To avoid rusting, do not knock the metal parts.
7.2.5 Usage of rubber rings
(1) Wires installed by field supply get through the rubber rings, such as 3-way valve, power cable
and so on. Be careful of separating electrical wire and light current wire.
(2) Tie the rubber rings after finishing wire connection.

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7.2.6 Safety operation of flammable refrigerant
(1) Qualification requirement for installation and maintenance man7 Installation of Hydraulic Unit
All the work men who are engaging in the refrigeration system should bear the valid certification
awarded by the authoritative organization and the qualification for dealing with the refrigeration system
recognized by this industry. If it needs other technician to maintain and repair the appliance, they should
be supervised by the person who bears the qualification for using the flammable refrigerant.
It can only be repaired by the method suggested by the equipment’s manufacturer.
(2) Installation notes
The unit is not allowed to use in a room that has running fire (such as fire source, working coal gas
ware, operating heater).
It is not allowed to drill hole or burn the connection pipe.
The unit must be installed in a room that is larger than the minimum room area.
Leak test is a must after installation.
Minimum
room area
(m2)
Charge amount(kg) ≤1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 22.1 2.2 2.3 2.4 2.5
floor location /14.5 16.8 19.3 22 24.8 27.8 31 34.3 37.8 41.5 45.4 49.4 53.6
window mounted /5.2 6.1 77.9 8.9 10 11.2 12.4 13.6 15 16.3 17.8 19.3
wall mounted /1.6 1.9 2.1 2.4 2.8 3.1 3.4 3.8 4.2 4.6 55.5 6
ceiling mounted /1.1 1.3 1.4 1.6 1.8 2.1 2.3 2.6 2.8 3.1 3.4 3.7 4
(3) Maintenance notes
Check whether the maintenance area or the room area meet the requirement.
It’s only allowed to be operated in the rooms that meet the requirement.
Check whether the maintenance area is well-ventilated.
The continuous ventilation status should be kept during the operation process.
Check whether there is fire source or potential fire source in the maintenance area.
The naked flame is prohibited in the maintenance area; and the “no smoking” warning board should
be hanged, nameplate.
Check whether the appliance mark is in good condition.
Replace the vague or damaged warning mark.
(4) Welding
If you should cut or weld the refrigerant system pipes in the process of maintaining, please follow
the steps as below:
1) Shut down the unit and cut power supply
2) Eliminate the refrigerant
3) Vacuuming
4) Clean it with N2gas
5) Cutting or welding
6) Carry back to the service spot for welding
The refrigerant should be recycled into the specialized storage tank.
Make sure that there isn’t any naked flame near the outlet of the vacuum pump and it’s
well-ventilated.

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15
(5) Filling the refrigerant
Use the refrigerant filling appliances specialized for R32. Make sure that different kinds of refrigerant
won’t contaminate with each other.
The refrigerant tank should be kept upright at the time of filling refrigerant.
Stick the label on the system after filling is finished (or haven’t finished).
Don’t overfilling.
After filling is finished, please do the leakage detection before test running; another time of leak
detection should be done when it’s removed.
(6) Safety instructions for transportation and storage
Please use the flammable gas detector to check before unload and open the container.
No fire source and smoking. According to the local rules and law
8 Optional Electric Heater
Optional electric heater is allowed for the equipment and controlled in such a way when outdoor
temperature is lower than the set point for startup of the optional electric heater.
Step 1. Optional electric heater installation
Optional electric heater should be installed with monobloc unit in series. The optional electric heater
could be 1group or 2 group, and only works of space heating.
Step 2. Electric wiring work
AC contactor should be installed to XT2 KM1(1 group electric heater) or KM1 and KM2(2 group
electric heater).
Step 3. Wired controller setting
Optional electric heater should be selected "1/2" group if necessary from COMMISION →
FUNCTION, then set switch on (outdoor)temperature and control logic(1/2).
9 Charging and Discharging of Refrigerant
The unit has been charged with refrigerant before delivery. Overcharging or undercharging will
cause the compressor to run improperly or be damaged. When refrigerant is required to be charged or
discharged for installation, maintenance and other reasons, please follow steps below and nominal
charged volume on the nameplate. Discharging: remove metal sheets of the outer casing, connect a
hose to the charging valve and then discharge refrigerant.

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NOTES:
(1) Discharge is allowed unless the unit has been stopped. (Cut off the power and repower it 1
minutes later)
(2) Protective measures should be taken during discharging to avoid frost bites.
(3) When discharging is finished, if vacuuming cannot be done immediately, remove the hose to
avoid air or foreign matters entering the unit.
(4) Vacuuming: when discharging is finished, use hoses to connect the charging valve, manometer
and vacuum pump to vacuum the unit.

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NOTE:
When vacuuming is finished, pressure inside the unit should be kept lower than 80Pa for at least 30
minutes to make sure there is no leak. Either charging valve 1 or charging valve 2 can be used for
vacuuming.
Charging: when vacuuming is finished and it is certain that there is no leak, charging can be done.
Leak Detection Methods:
(1) The following leak detection methods are deemed acceptable for systems containing
flammable refrigerants.
(2) Electronic leak detector shall be used to detect flammable refrigerant, but the sensitivity may
not be adequate, or may need re-calibration (Detection equipment shall be calibrated in a
refrigerant-free area).
(3) Ensure that the detector is not a potential source of ignition and is suitable for the refrigerant
used.
(4) Leak detection equipment shall be set at a percentage of the LFL of the refrigerant and shall be
calibrated to the refrigerant employed and the appropriate percentage of gas (25% maximum)
is confirmed.
(5) Leak detection fluids are suitable for us with most refrigerant but the use of detergents
containing chlorine shall be avoided as the chlorine may react with the refrigerant and corrode
the copper pipe-work.
(6) If a leak is suspected, all naked flames shall be removed / extinguished. If a leakage of
refrigerant is found which requires brazing, all of the refrigerant shall be recovered from the
system, or isolated (by means of shut off valves) in a part of the system remote from the leak.
Oxygen free nitrogen (OFN) shall then be purged through the system both before and during
the brazing process.
NOTE:
Before and during operation, use an appropriate refrigerant leak detector to monitor the operation area
and make sure the technicians can be well aware of any potential or actual leakage of inflammable gas.
Make sure the leak detecting device is applicable to inflammable refrigerant. For example, it should be
free of sparks, completely sealed and safe in nature.
10 Installation of Insulated Water Tank
10.1 Selection of Water Pipe
Inlet and outlet water pipe diameter of the unit shall be determined by the rated flow of the unit and
the recommended flow speed velocity. Flow speed of hot water pipeline shall refer to the following table.
Nominal diameter(mm) 15~20 25~40 ≥50
Flow velocity(m/s) ≤0.8 ≤1.0 ≤1.2