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MCAC-RTSM-2011-12 Midea Combo Type Heat Pump Water Heater Technical Manual
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Midea Combo Type
Heat Pump Water Heater
Technical Manual
Applicable Model:
RSJ-15/190RDN3-D
RSJ-35/300RDN3-D
Midea reserves the right to discontinue, or change at any time, specifications or designs without notices and
without incurring obligations.
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Contents
Part 1 General Information .................................................. 3
1. Measurements ................................................................................ 4
2. External Appearance ..................................................................... 4
3. Nomenclature ................................................................................. 5
4. Features .......................................................................................... 6
Part 2 Combo Units .............................................................. 7
1. Specifications ............................................................................. 8
2. Operation range ........................................................................ 10
3. Performance diagram ................................................................ 11
4. Dimensions ............................................................................... 13
5. Service Space ................................ ................................ ........... 14
6. Wiring Diagrams ....................................................................... 15
7. Piping Diagrams ....................................................................... 17
8. Duct connection ....................................................................... 18
9. Exploded View .......................................................................... 19
Part 3 Installation ............................................................... 23
1. Precautions .................................................................................. 24
2. Installation information ............................................................... 25
3. Unit Appearance and Composition ............................................ 27
4. Accessories ................................................................ .................. 29
5. Inspecting and Handling the Unit ............................................... 29
6. Electric Wiring ................................................................ .............. 29
Part 4 Trial Operation ........................................................ 31
1. Confirmation Before the Trial Operation ................................ .... 32
2. Operation Instruction .................................................................. 32
3. PCB explanation .......................................................................... 43
4. Maintenance .................................................................................. 45
5. Malfunctions and Resolutions .................................................... 46
6. Malfunction Code and Troubleshooting ..................................... 46
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Part 1
General Information
1. Measurements .................................................................. 4
2. External Appearance ....................................................... 4
3. Nomenclature ................................................................... 5
4. Features ............................................................................ 6
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1. Measurements
Model
Dimension
(mm: D x H)
Net weight / Gross weight
(kg)
Power Supply
RSJ-15/190RDN3-D
Φ568×1640
94/110
220~240V-1ph-50Hz
RSJ-35/300RDN3-D
Ф650×1,920
123/150
220~240V-1ph-50Hz
2. External Appearance
RSJ-15/190RDN3-D RSJ-35/300RDN3-D
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3. Nomenclature
Household Water Heating Unit
1
2 3
-
/
- 5
Rated hot water output, unit: 100 W
6
7
8
Power supply specification code
Heating mode code
Water tank volume, unit: L
9
Other functions code
10
11
12
-
Water supply pump lift code
Refrigerant code
Design code
Installation type code
Water heating unit code
Export model code
For example:
RSJ-15/190 R D N3 - D
Design code
Refrigerant type (R134a)
Other function (E-heater)
Cycle-heating Type (refrigerant cycle)
Water storage (190L)
Heating Capacity (1500W)
Midea Heat Pump water heater
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4. Features
4.1 Safety
a. Complete isolation between water and electricity. No
electric shock problem, more safety.
b. No fuel tubes and storage, no potential danger from oil
leakage, fire, explosion etc.
c. No cross contamination potential, the condenser coil
wrapped around the stainless steel inner tank
4.2 Max. outlet water Temperature: 70℃.
The system is adopted innovative heating methods: combined the Electric heating and Heat Pump
heating properly, made the water be heated stably and quickly.
4.3 Flexible installation achieved by long air intake/outlet duct with pressure
4.4 Automatic Control:
Automatic start-up and shutdown, automatic defrosting by revising refrigerant cycle. Save you much extra
operation.
4.5 High Efficiency and Energy Saving.
The unit adopts heat pump principle, which absorbs heat from outdoor air and produce heat water, thermal
efficiency can be approximately 3.6 (under the condition A15/12 W15/45)
4.6 All-the-weather Running.
Within the temperature range from -30 to 43℃, it will not be affected by night, cloudy sky,
rain even snow whether.
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Part 2
Combo Units
1. Specifications .............................................................. 8
2. Operation range......................................................... 10
3. Performance diagram ............................................... 11
4. Dimensions ................................................................ 13
5. Service Space ............................................................ 14
6. Wiring Diagrams ........................................................ 15
7. Piping Diagrams ........................................................ 17
8. Duct connection ........................................................ 18
9. Exploded View ........................................................... 19
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1. Specifications
Model
RSJ-15/190RDN3-D
Running mode
Economy
E-heater
Running ambient temp.
℃
-7～43
-30～43
Outlet water Temp.
℃
Default 55℃,38℃～70℃
Power supply
Ph-V-Hz
1-220～240-50
Storage size
L
190
Water heating
Capacity
kW
1.5
3.00
Cop
kW/kW
3.6
1.00
Max. current A 3.4
13.0
Ambient temp.
℃
-30～43
Unit
Dimension (D×H)
mm
Φ568×1640
Packing (W×H×D)
mm
675×1715×690
Net/gross weight
kg
94/110
Noise level
dB(A)
41
Refrigerant type/quantity
kg
R134a/0.95
Refrigerant design
pressure
MPa
2.6/ 1.2
Tank design pressure
MPa
0.15～1.0
Throttling type
Electronic expansion valve
System protection
TCO1, TCO2, PT valve, automatic defrosting,
over-load protector temp. electric leakage protector
Air flow(with filter screen)
m³/h
218/202/178
Compressor
Model
PJ125G1C-4DZDE
Type
Rotary
Brand
GMCC
Capacity
Btu/h
4740
Input
kW
0.515
Rated current(RLA) A 2.32
Locked rotor Amp(LRA) A 15
Thermal protector
125
Capacitor
μF
25
Refrigerant oil
ml
400
Fan motor
Model
YDK12-6A
Brand
welling
Input
w
28
Speed
r/min
900/815/680
Insulation class
B
Safe class
IPX4
Input
W
28
Output
W
9
Rated current
A
0.12
Capacitor
μF
1.2
Indoor coil
Number of rows
3
Tube pitch(a)x row
pitch(b)
mm
21*13.37
Fin spacing
mm
1.5
Fin type (code)
hydrophilic aluminum
Tube outside dia. and type
mm
φ7
internal screw thread
Coil length x height
mm
402.4*294
Number of circuits
3
Water pipeline
Water inlet pipe
mm
DN20
Water outlet pipe
mm
DN20
Drainage pipe
mm
DN20
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PT valve joint
mm
DN20
Max. pressure
MPa
1.2
Design pressure
MPa
0.15～1.0
Heat exchanger
Dividing wall type heat exchanger
E-heater
kW
3.0
Hot water yield
m³/h
0.043
0.086
Loading Quantity
20'/40'/40H
Pcs
24/51/51
Remark:
1. The test conditions: outdoor temp. 15/12℃(DB/WB), inlet water temp. 15℃, outlet water temp.45℃.
2. The specification may be changed for product improvement, please refer to the nameplate.
Model
RSJ-35/300RDN3-D
Running mode
Economy
E-heater
Running ambient temp.
℃
-7～43
-30～43
Outlet water Temp.
℃
Default 55℃,38℃～60℃
Power supply
Ph-V-Hz
1-220～240-50
Storage size
L
300
Water heating
Capacity
kW
3.00
3.00
Cop
kW/kW
3.60
1.00
Max. current A 6.5
13.0
Ambient temp.
℃
-30～43
Unit
Dimension (D×H)
mm
Ф650×1,920
Packing (W×H×D)
mm
750×2,150×780
Net/gross weight
kg
123/150
Noise level
dB(A)
48
Refrigerant type/quantity
kg
R134a/1.2
Refrigerant design
pressure
MPa
3.0/1.2
Tank design pressure
MPa
1
Throttling type
Electric expansion valve
System protection
TCO1, TCO2, PT valve, automatic defrosting, over-load
protector temp. electric leakage protector etc.
Air flow
m³/h
414/355/312
Compressor
Model
RB233GRDC
Type
Rotary
Brand
Guangzhou Mitsubishi electric
Capacity
Btu/h
9500
Input
kW
0.9
Rated current(RLA)
A
4.1
Locked rotor Amp(LRA) A 30
Thermal protector
115
Capacitor
μF
30
Crankcase
W
25
Refrigerant oil
ml
440
Fan motor
Model
YDK30-6R
Brand
welling
Input
w
68
Speed
r/min
620/530/465
Insulation class
B
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Safe class
IPX4
Rated current
A
0.3
Capacitor
μF
2.5
Evaporator coil
Number of rows
3
Tube pitch(a)x row
pitch(b)
mm
22×19.05
Fin spacing
mm
1.5
Fin type (code)
hydrophilic aluminum
Tube outside dia. and
type
mm
8
internal screw thread
Coil length x height
mm
482×352
Number of circuits
4
Water pipeline
Water inlet pipe
mm
DN20
Water outlet pipe
mm
DN20
Drainage pipe
mm
DN20
PT valve joint
mm
DN20
Heat exchanger
Dividing wall type heat exchanger
Solar heat exchanger
Water inlet pipe
mm
DN20
Water outlet pipe
mm
DN20
Heat exchanger
Stainless steel SUS316L
Dim.× Length
mm
22×10000
Max. pressure
MPa
0.7
E-heater
kW
3
Hot water yield
m³/h
0.086
Loading Quantity
20'/40'/40H
Pcs
21/47/47
Remark:
1. The test conditions: outdoor temp. 15/12℃(DB/WB), inlet water temp. 15℃, outlet water temp.45℃.
2. The specification may be changed for product improvement, please refer to the nameplate.
2. Operation range
E-heater running ambient temperature range: -30~45℃.
Heat pump running ambient temperature range: -7~43℃.
Water temperature limits:
Ambient temp. T4
Model
T4＜-7
-7≤T4＜-2
-2≤T4＜2
2≤T4＜7
7≤T4＜43
43≤T4
RSJ-15/190RDN3-D
Max temp
(Heat pump)
—
45
60
70
70
—
Max temp
(E-heater)
70
70
70
70
70
70
RSJ-35/300RDN3-D
Max temp
(Heat pump)
—
42
47
55
60
—
Max temp
(E-heater)
60
60
60
60
60
60
Note：Modes will be automatically selected by the unit. manually mode selection is unavailable
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3. Performance diagram
3.1 The relationship between capacity and ambient temperature
Model: RSJ-15/190RDN3-D
Model: RSJ-35/300RDN3-D
1.00
1.50
2.00
2.50
3.00
3.50
4.00
4.50
5.00
-7 -2 2 7 10 15 20 25 30 35 40 43
(kw)
15--45 15--50 15--55 15--60
3.2 The relationship between COP and ambient temperature
Model: RSJ-15/190RDN3-D
Ambient temp(℃)
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Model: RSJ-35/300RDN3-D
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4. Dimensions
Model ：RSJ-15/190RDN3-D
Model ：RSJ-35/300RDN3-D
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5. Service Space
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6. Wiring Diagrams
Model：RSJ-15/190RDN3-D
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Model：RSJ-35/300RDN3-D
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7. Piping Diagrams
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8. Duct connection
A: Air inlet and outlet without duct B: Only air outlet with canvas, A≤5m
It is recommended to install unit by this way in the winter
where there is other heat source in the room.
C: Air inlet and outlet with duct. (A+B≤5m) D: Only air inlet with canvas A≤5m
It is recommended to install unit by this way in summer
that could charge fresh air into room
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9. Exploded View
Model : RSJ-15/190RDN3-D
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No.
Part Name
No.
Part Name
1
Upper back cover
14.18
Inner enamel components
2
Filter
14.19
Tank cover ass'y
3
Ring
15
Front decorative boards
4
Barbed wire
16
Heater cover on
5
Barbed wire
17
Under the heater cover
6
Top cover
18
Temp.sensor ass'y
7
top front sheet
19
Temp.sensor ass'y
8
front volute
20
Temperature control waterproof cover
9
Display cover
21
Electronic expansion valve ass'y
10
Display panel
22
Pressure line cover
11
Motor
23
4-way valve ass'y
12
Centrifugal wind wheel assembly
24
Evaporator ass'y
13
back volute
25
Discharge temp sensor ass'y
14
Foam tank ass'y
26
Junction box cover
14.1
Temperature and pressure safety
valve
27
Room temp sensor ass'y
14.2
Water Outlet pipe
28
Junction box cover
14.3
Electric heating foam baffle
28.1
Wire joint, 3p
14.4
Thermometer
29
Compressor
14.5
Stator of temp. sensor
30
E-part box ass'y
14.6
Temp sensor
30.1
E-part box
14.7
Electric heating pipe water
30.2
Main control board ass'y
14.8
Water Inlet pipe
30.3
Transformer
14.9
Magnesium rod
30.4
Dual Relay
14.10
Supporting plastic tank block
30.5
Relay
14.11
Foam
30.6
Insert motor capacitor
14.12
Drain plug
30.7
Wire joint,2p
14.13
Tank bottom
30.8
Compressor capacitor
14.14
PT valve loop
30.9
Capacitor clamp
14.15
Tank shell
31
Electric control the lid
14.16
Water tank handle
32
Display board ass'y
14.17
Welded pipe temperature
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Model : RSJ-35/300RDN3-D
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No.
Part Name
No.
Part Name
1
The wind ring
16.7
Relay
2
Filter
17
Electronic Control Box Bracket
3
Net
18
Deck board
4
The front cover
19
On the heater cover
5
cover
20
Deck magnet
6
Magnesium rod plug
21
Magnet clip
7
Junction box cover
22
Magnet cover
8
Motor
23
4-way valve ass'y
9
Display panel
23.1
Pipe joint
10
Display board ass'y
23.2
Pressure controller
11
Centrifugal fan
23.3
4-way valve
12
Display cover
23.4
Solenoid
13
E-Part box cover
24
Electronic expansion valve ass'y
14
Tank foam components
24.1
EEV solenoid
14.1
Tank cover assembly
24.2
Solenoid valve winding
14.2
Froth plug
24.3
Electronic expansion valve
14.3
Temp sensor
24.4
Solenoid valve
14.4
Magnesium anode
25
Compressor
14.5
Thermometer
26
Discharge temp sensor ass'y
14.6
Stator of temp. sensor
27
Room temp sensor ass'y
14.7
Electric heating pipe water
28
Temp.sensor ass'y
14.8
seal ring of radiation pipe
29
Temperature sensor
14.9
Seal Stopper
32
Compressor electric heater
14.10
Drain plug assembly
33
Evaporator ass'y
14.11
Tank bottom cover
33.1
Evaporator
14.12
PT valve loop
33.2
Evaporator output pipe ass'y
14.13
Water tank handle
33.3
Evaporator input pipe ass'y
14.14
TP safety valve
35
Before scroll
15
Magnet frame
36
Compressor wire joint ass'y
16
E-part box ass'y
37
Screw plate
16.1
E-part box
39
Drain
16.2
Compressor capacitor
40
After the cover on
16.3
Main control board ass'y
41
Dry Filter
16.4
Transformer
42
Plumbing fixture
16.5
Motor capacitor
43
Electronic control box panels
16.6
Wire joint
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Part 3
Installation
1. Precautions ................................................................... 24
2. Installation information ................................................. 25
3. Unit Appearance and Composition .............................. 27
4. Accessories ................................................................... 29
5. Inspecting and Handling the Unit ................................ 29
6. Electric Wiring ............................................................... 29
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1. Precautions
To prevent injury to the user or other people and property damage, the following instructions must be
followed. Incorrect operation due to ignoring of instructions may cause harm or damage.
The safety precautions listed here are divided into two categories. In either case, important safety
instructions are listed to which close attention must be paid.
WARNING
Failure to observe a warning may result in death.
CAUTION
Failure to observe a caution may result in injury or damage to the equipment.
WARNING
The unit must be earthed effectively.
A creepage breaker must be installed adjacent to the power supply
Do not remove, cover or deface any permanent instructions, labels or the data label from either the
outside of the unit or inside of unit panels.
Ask qualified person to perform the installation of this unit in accordance with local national regulations
and this manual.
Improper installation may result in water leakage, electric shock or fire.
Do not insert fingers, rods or other objects into the air inlet or outlet. When the fan is rotating at high
speed, it will cause injury.
Never use a flammable spray such as hair spray, lacquer paint near the unit. It may cause a fire.
Ask qualified person for relocating, repairing and maintaining the unit instead of doing by yourself.
Improper installation may result in water leakage, electric shock or fire.
Electric connection work should obey the instructions of local power company, local electric utility and
this manual.
Never use the wire and fuse with wrong rated current, otherwise unit may break down and cause fire
furthermore
The appliance should not be used by children without supervision .If the supply cord is damaged, it must
be replaced by the manufacturer or its service agent or a similarly qualified person.
DISPOSAL:
Do not dispose this product as unsorted municipal waste. Collection of such waste separately for
special treatment is necessary.
Do not dispose of electrical appliances as unsorted municipal waste, use separate collection facilities.
Contact your local government for information regarding the collection systems available.
If electrical appliances are disposed of in landfills or dumps, hazardous substances can leak into the
groundwater and get into the food chain, damaging your health and well-being.
CAUTION
The earthing pole of socket must be grounded well, the rated current should be no less than 15A, make
sure that power supply socket and plug are dry enough and connected tightly.
How to check the power supply socket and plug are qualified?
Turn on power supply and keep the unit running for a half hour, then turn off power supply and plug out,
check whether the socket and plug is hot or not.
Before cleaning, be sure to stop the operation and turn the breaker off or pull out the power plug.
Otherwise, an electric shock and injury may be caused.
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Water temperature over 50℃ can cause severe burns instantly or death from scalds. Children, disabled
and elderly are at highest risk of being scalded. Feel water before bathing or showering.
Water temperature limiting valves are recommended.
Do not operate the unit with a wet hand. An electric shock may be caused.
The installation height of power supply should be over 1.8m, if there is any water spattered, separate
the power supply from water.
A one-way valve must be installed on the water inlet side, which is available from accessories, see
manual "accessories" part.
It’s normal if some water drops from the hole of PT valve during operation. But, if there is a great
amount of water, call your service agent for instructions.
After a long term use, check the unit base and fittings. If damaged, the unit may sink and result in injury.
Arrange the drain pipe to ensure smooth draining. Improper drainage work may cause wetting of the
building, furniture etc.
Do not touch the inner parts of the controller.
Do not remove the front panel. Some parts inside are dangerous to touch, otherwise a machine
malfunction may be caused.
Do not turn off the power supply.
2. Installation information
Enough space for installation and maintenance shall be preserved.
The air inlet and outlet should be free from obstacles and strong wind.
The base surface should be flat, surface should be inclined no more than 2°and able to bear weight of
the unit and suitable for installing the unit without increasing noise or vibration.
The operation noise and air flow expelled shall not affect neighbors.
No flammable gas is leaked nearby.
It is convenient for piping and wiring.
If it is installed in indoor space, it might cause indoor temp decreased and noise, Please take preventive
measures for this.
If the unit has to be installed on a metal part of building, make sure the well electric insulation which
should meet the relevant local electric standard.
CAUTION
The ambient air temperature must also be considered when installing this unit, in Heat pump mode the
ambient air temperature must be above -7℃ and below 43℃if the ambient air temperature falls outside
these upper and lower limits, the electrical elements will activated to meet the hot water demand and
the heat pump does not operate.
The unit should be located in an area not subject to freezing temperatures. The unit located in
unconditioned space (i.e. garages, basements, etc.) may require the water piping, condensate piping,
and drain piping to be insulated to shelter against freezing.
Installing the equipment in any of the following places may lead to malfunction of the equipment (if it is
inevitable, consult the supplier):
1) The site contains mineral oils such as cutting lubricant.
2) Seaside where the air contains much salt.
3) Hot spring area where corrosive gases exist, e.g., sulfide gas.
4) Factories where the power voltage fluctuates seriously.
5) Inside a car or cabin.
6) Place like kitchen where oil permeates.
7) Place where strong electromagnetic waves exist.
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8) Place where flammable gases or materials exist.
9) Place where acid or alkali gases evaporate.
10) Other special environments.
Precautions before installation
1) Decide the correct way of conveying the equipment.
2) Try to transport this equipment with the original package.
3) If the unit has to be installed on a metal part of the building, electric insulation must be installed, and the
installation must meet the relevant technical standards for electric devices.
Installation space
Before installing the unit, reserve the space of maintenance .
WARNING
■ Ask your supplier to install the air source heat pump water heating units. Incomplete installation
performed by yourself may result in a water leakage, electric shock, or fire.
■ The place without direct sunlight and other heat supplies. If there’s no way to avoid these, please install
a covering.
■ The unit must be securely fixed, or else, noise and shaking will be resulted.
■ Make sure that there’s no remora around the unit.
■ In the place where there is strong wind like seashore, fix the unit in the location protected from the wind.
■ Carry the unit onto the site
1) In order to avoid scratch or deformation of the unit surface, apply guard boards to the contacting
surface.
2) No contact of fingers and other things with the vanes.
3) Don’t incline the unit more than 45° in moving, and keep it vertical when installing.
■ Install the unit.
1) The circulating air for every unit should be more than 700m3/h.
2) Make sure there is enough Installation space.
3) Outline dimensional drawing
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3. Unit Appearance and Composition
Model : RSJ-15/190RDN3-D
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Model : RSJ-35/300RDN3-D
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4. Accessories
Check whether the following assemblies are complete.
5. Inspecting and Handling the Unit
After delivery, the package should be checked and any damage should be reported immediately to the
carrier claims agent.
When handling the unit, take into account the following:
1. Fragile, handle the unit with care.
Keep the unit upright in order to avoid compressor damage.
2. Choose before hand the path along which the unit is to be brought in.
3. Move this unit with original package.
4. When lifting the unit , always use protectors to prevent belt damage and pay attention to the balance of
the unit’s gravity.
6. Electric Wiring
6.1 Attention
● The water heater should powered separately and the power voltage should be in line with rated voltage..
● The power supply circuit of the water heater should be earthed, the power cord should be connected
with the external earthing line in reliable state and all the external earthing cables are effective.
● The construction of the wiring should be carried out by professionals in accordance with the circuit diagram.
● Set up leakage protection devices in accordance with the requirements of the relevant national
technical standards.
● The power cord and the signal line should be laid neatly without cross-interfere and should not contact
with the connecting pipe and the valves.
● The unit is not equipped with power cord. Please refer to the prescribed power specification for
selecting the power cord and cross-connection between two lines are not allowed.
● Check whether all the connections are correct before powering the unit.
6.2 Power specification
Model
RSJ-15/190RDN3-D
RSJ-35/300RDN3-D
Power Supply
220-240V～50Hz
220-240V～50Hz
Min Diameter of Power Supply cord ( mm2 )
4 4 Earth cord (mm2)
4
4
Manual switch(A)capacity / Fuse
25 / 20
25 / 20
Creepage Breaker
30 m A ≤ 0. 1sec
30 m A ≤ 0. 1sec
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6.3 Power Supply Wiring .
A. Power Supply Schematic Diagram
Warming:
Although there is a leakage protector in the electric control box of the unit, for the security reason, it is
required that a leakage protection equipped cable and Earthing should be applied for the unit according to
the requirement on the above diagram.
B. Cable Diameter Selection
The power supply wiring refers to the wiring to the main line (a) of junction box and the wiring (b) to the
power supply equipment. Please select the cable diameter according to the following methods
1) Diameter of the main line (a):
Get from the power supply specification table according to the sum of horsepower of the unit.
2) Diameter of the wiring from the junction box to the power supply equipment:
When the water heaters are less than 5 sets, the diameter the wiring from the junction box to the power
supply equipment should be the same as the main line (a); when the water heaters are more than 6 sets, the
power supply equipment should have two sets of electric control box and the diameter should be get from
the power supply specification table according to the sum of horsepower of the units connected by the
electric control box.
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Part 4
Trial Operation
1. Confirmation Before the Trial Operation ...................... 32
2. Operation Instruction .................................................... 32
3. PCB explanation ............................................................ 43
4. Maintenance .................................................................. 45
5. Malfunctions and Resolutions .................................... 46
6. Malfunction Code and Troubleshooting ..................... 46
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1. Confirmation Before the Trial Operation
1.1 All the installation is complete.
1.2 Water heater is installed correctly.
1.3 The pipelines and wiring are correct.
1.4 The accessories are installed correctly.
1.5 The drainage is smooth.
1.6 The thermal insulation is sound.
1.7 The earthing wire is connected correctly.
1.8 The power voltage is consistent with the rated voltage of the heater.
1.9 No obstacle at the air inlet and outlet of the unit.
1.10 The leakage protector can work effectively.
2. Operation Instruction
2.1 Instruction
2.1.1 Before using this unit, please follow the steps below.
Water affusion: If the unit is used for the first time or used again after emptying the tank, please make sure
that the tank is full of water before turning on the power. Method: see figure 2.1.1
Hot water outlet
Close
Water out
When water flows out from the water
outlet, the tank is full.
Turn o
ff the hot
water outlet valve and water a
ffusion
is finished.
Hot water outlet
Cool water inlet
Open
Open the cool water inlet and
hot water outlet
Open
Water Affusion
NOTE:
1. The Ball Valve at water inlet should be open when the unit is in operation.
2. Operation without water in water tank may result in damage of auxiliary e-heater. Due to such damage, the supplier is not
responsible for the quality issue.
3. Over 50℃ may result in serious burn or so caused death. Special care should be paid to the children, the disabled and
the old in case of water burn.
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2.1.2 After powered on, the display lights up. Users can operate the unit through the buttons under the
display for different modes. Emptying: If the unit needs cleaning, moving etc, the tank should be
emptied. Method: See Figure 2.1.2
Close
Open
Drainpipe
Open
Cool water inlet
Hot water outlet
Close the cool water inlet, open the hot
drainpipe.
water outlet and open the nut of
After emptying, please close the nut
of drainpipe
Close
Drainpipe
Emptying
NOTE: The outlet water temp. may be very high when emptying, beware of your body for burns.
2.2 Operation
2.2.1 Control Panel Explanation
2.2.2 Display Explanation
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Icon
Description
Wire controller:
If connected a wire controller, it will be lightened; otherwise it will be extinguished
Outside solar heat source:
If an outside solar heat source has been connected to the unit, it will flash with 1 Hz
frequency; otherwise it will be extinguished.
Vacation mode:
This icon will be lightened if the unit is under vacation mode and flash with 2Hz frequency
when setting vacation mode.
Compressor:
This icon will be lightened when compressor is running, otherwise it will be extinguished.
E-heater:
This icon will be lightened if e-heater is activated, otherwise it will be extinguished.
If e-heater is automatically activated by unit, it will be lightened;
If e-heater is manually activated, it will flash with 1Hz frequency.
When setting e-heater manually ON/OFF, it will flash with 2 Hz frequency.
Disinfect:
This icon will be lightened when the unit is under disinfect mode, otherwise it will be
extinguished.
This icon will be lightened if disinfect mode is automatically activated by unit; it will flash
with 1Hz frequency, if disinfect mode is manually activated; it will flash with 2Hz frequency
when setting disinfect mode or setting disinfect timer.
High temp. Alarm
If setting water temp. is higher than 50℃，it will be lightened, otherwise will be extinguished.
Alarm:
When unit is under protection/error, it will flash, it with 5Hz frequency as well as buzzer will
sound 3 times every 1 minute until protection/error eliminated or press for cancel button 1
second
Lock:
If button is locked, this icon will be lightened, otherwise it will be extinguished.
Temperature unit
If setting temperature unit as Celsius, ℃will be lightened;
If setting temperature unit as Fahrenheit, ℉will be lightened
If button is under lock mode, press any button except unlock button, this icon will be
lightened
This icon will be lightened if screen is unlocked.
It shows water temperature on normal mode;
It shows remaining vacation days on vacation mode;
It shows setting temperature under setting mode;
It shows unit setting/running parameters, error/protection code under query mode
Reserved
Water Temperature setting
This icon will be lightened when setting water temperature or setting days for vacation.
Date setting
This icon will be lightened when setting days for vacation;
It will be lightened when under vacation mode.
Timer
There are six timers can be set.
If anyone of them has been set, this icon will lighten the corresponding one when screen is
unlocked；
If there is none of timer has been set, it will keep extinguished.
If timer is being set, the icon will flash the corresponding one with 2HZ frequency as well
lighten the timer which has been set.
Clock and clock setting
This icon shows the clock. Whenever there is any setting for clock, it will be lightened.
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2.2.3 Operation Instruction
2.2.3.1 Preparation before running the unit.
a) When you run the unit for the first time, all the indicators on the UI will light for 3 second, and the
buzzer will “didi” ring twice at the same time, and then, display the fiducially web page. After no
operation for 1 minute, button will be locked except Unlock button( ), Press for 3s, unlock buttons.
b) When the tank is full and make sure all settings finished, please press the ON\OFF key and then
run the unit.
c) When the unit is running, if there is no operation or malfunction for 30s, screen will be locked
(extinguished) except for error code and alarm light. Press any button will unlock the
screen(lighten).
2.2.3.2 Lock and Unlock
In order to prevent wrong operation, a special lock function has been designed. If there is no operation for
1min, the unit will be locked automatically, and display the lock sign (Lock indicator lights up).When the unit
is locked, no keys can be operated.
2.2.3.3 Clock Setting
The clock is for a 24-hour system and the initial time is 00:00. To make a better use of this unit, it is
recommended to set the time for accurate local time. Every time powered off, the clock will be reset to the
initial time 00:00.Method for time set
2.2.3.4 Mode Selection
a) The unit is enhanced with four operation modes, Economy Mode, Vacation, Disinfect and E-heater
Mode.
b) Economy Mode: this mode is the default mode, the unit heats water only by compressor drive
according to heat-pump principle.
c) E-heater Mode: After pressing " E-heater " button, the unit heats water only by electric heater. Used
when the ambient temp. is too low.
Press for 3s
to unlock the button
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d) Vacation Mode: After pressing "Vacation" button, the unit will automatically heat water to 15℃ for
the purpose of energy saving during vacation days.
e) Disinfect Mode: After pressing " Disinfect " button, the unit immediately start to heat water up to
65℃ to kill the potential legionella bacteria inside water of tank.
2.2.3.5 Temperature Setting
Temp displayed is the water temp. in the upper part of the tank. Default is 55℃.
Method for set.
2.2.3.6 TIMER
User can set up a running start time and a stop time on a specifically by the timer function. The least
numbers of timer is ten minutes. Time on: User can set up a start time by this. The unit will auto run one time
between the set time and 24:00 on the same day.
Method for set.
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CANCEL:
CHECK:
2.2.3.7 Power On and Power Off
Press “On/ Off” button after all the above have finished and the system will run as the setting. And simply
press the same button to stop it.
2.2.3.8 Operation status
The LA code from the screen of set Temp. will appear and remind user when ambience temp. not meet the
operation condition of heat pump unit(beyond -7～43℃)，User can switch the economy mode to E-heating
mode in sure of enough volume of hot water if need, The unit will return operation pre-status automatically
in no any operation when the ambient temp. meet the operation condition of heat pump mode and the error
LA will be disappear at the same time, the screen display normally.
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2.2.3.9 Error Shooting
If some errors happen, the buzzer will buzz 3 times every other minute and the error indicator will glitter fast.
Press CANCEL for several seconds to stop the buzzer but the light will keep glittering.
ALARM
The light will flash with Alarm
Press CANCEL key to stop the buzzer.
When error happens, though the system could be used in some circumstances, it could not reach the
expected efficiency. Please contact your supplier for help. Error Code Explanation (See table below table)
Display
Malfunction Description
Display
Malfunction Description
E0
Error of sensor T5U
P1
System high pressure protection
≥2.76MPa active；
≤2.07Mpa inactive
E1
Error of sensor T5L
P2
High discharge temp. protection
Tp>115℃，Protection active
Tp<90℃，Protection inactive
E2
Tank and Wired Controller communication
error
P3
Compressor abnormally stopped protection
The discharge temperature is not so higher than
evaporator temperature after compressor running a
term.
E4
(T3) Condenser output pipe temperature
sensor error
P4
Compressor overloaded protection (10 sec after
compressor startup, Current checking starts ,
1)only compressor running, if it is >7A , the
compressor will be stopped and protected.)
2)Compressor+ e-heater opened, if it is >IEH+7,the
compressor will be stopped and protected.)
E5
(T4) Outdoor ambient temperature sensor
error
LA
When the ambient temp is out of Heat Pump running
zone [-7～43℃],Heat Pump will stop ,then LA
protection code will appear, and ALARM indicator
flashes if the condition maintain more than 20
hours, Need to switch to Enhanced heating Mode.
E6
(Tp) Comp. discharge Sensor error
E9
Compressor suction temperature sensor TH error
E7
Heat Pump system error
If any of P3/P4/P2/P1 continuously appear 3
times within single heating cycle, system will
consider it as “Heat Pump system error”
Ed
EEPROM chip error
EE
E-heater open-circuit error( IEH(Current difference
E-heater on & e-heater off )<1A)
E8
Electric leakage error
If PCB current induction circuit check the
current difference between L,N >14mA,
system consider it as” electric leakage error”
EF
Clock chip error
2.3 Running and Operating
2.3.1 Trial Running
1) Before running, please check the following items first:
2) Correct installation of the system;
3) Correct connection of pipeline and wiring;
4) Leakage of the refrigerant pipeline tested;
5) Efficient drainpipe;
6) Complete insulation protection;
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7) Correct earthing;
8) Correct power supply;
9) No obstacle outside the air inlet and outlet;
10) No air in the water pipeline and all valve opened;
11) Effective electric leakage protector;
12) Sufficient inlet water pressure(≥0.15MPa)
2.4 Refrigerant figure
2.4.1 System Piping figure
Model : RSJ-15/190RDN3-D
Compressor : GMCC PJ125G1C-4DZDE, R134a compressor；
ATCO (Temp. Switch): If the water temperature is too high. If the temperature is higher than 78℃, the
ATCO will automatically shut off the power of compressor and E-heater, and turn on it if the temperature
fall down below 68℃;
TCO (Temp. Switch): If the water temperature is higher than 85℃, the TCO will automatically shut off
the power of compressor and E-heater, it must be re-turn on manually.
High Pressure Switch: switch OFF when 2.76MPa; switch ON when 2.07MPa;
Fan: Centrifugal type, 220V—240V/50Hz，3 Speeds;
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Model: RSJ-35/300RDN3-D
Compressor: Mitsubishi RB233GRDC, R134a compressor；
E-heater: Located in the mid of tank, 3000W/230VAC;
ATCO (Temp. Switch): If the water temperature is too high. If the temperature is higher than 78℃, the
ATCO will automatically shut off the power of compressor and E-heater, and turn on it if the temperature
fall down below 68℃;
TCO (Temp. Switch): If the water temperature is higher than 85℃, the TCO will automatically shut off
the power of compressor and E-heater, it must be re-turn on manually.
High Pressure Switch: switch OFF when 2.76MPa; switch ON when 2.07MPa;
Fan: Centrifugal type, 220V—240V/50Hz，3 Speeds;
2.4.2 System I/O figure
PCB
Evaporator Temp. T3
Ambient Temp. T4
Discharge Temp. Tp
Suction Temp. Th
Upper tank Temp. T5U
Lower tank Temp. T5U
Electric control box temp.(preserved)
High pressure protection
Remote On/Off signal input(preserved)
Middle tank temp.(preserved)
Wire
controller
Display
Panel
Comp.
4-way valve
Fan motor (3 speed)
Comp. heater
EEV
Element
Element(preserved)
Electric control box fan (preserved)
Remote On/Off signal output(preserved)
2.4.3 Fan motor speed control
Fan motor speed has 3 levers, High, Middle, Low speed;
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Fan motor will start with high speed 30s in advance of the start of compressor;
After staring, Fan motor speed will be regulated by Tp ( Compressor discharge temperature) with
following logic
100
105
Tp
95
Fan motor will stop 30s behind of the stop of compressor
2.4.4 Defrosting during Water-heating
Conditions to activate defrosting cycle
When T3 ≤0℃, Comp. is continually running for 40min
(If Comp. restart frequently, which can only run within 10 min. for each start cycle, system will count
accumulated running time, when accumulated running time reaches 40min, defrosting cycle will activate 2
min. after Compressor’s next start
Conditions to inactivate defrosting cycle (when achieve any one of following conditions)
1. Defrosting time reaches 10 min;
2. T3≥15℃;
Main components’ movement when defrosting
2.4.5 Ambient Temperature
a) The system’s operation temperature is within -30~43℃ and below are the operation temperature for
each mode.
b) Economy Mode: -7~43℃
c) E-heater Mode: -30~43℃
2.4.6 Self-Protection Detection
a) When the self-protection happens, the system will be stopped and start self-check, and restart when the
protection resolved;
Low Speed
Middle Speed
High Speed
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b) When the self-protection happens, the buzzer will buzz in every other minute, the Warning indicator
glitter and the display indicate the error code and water temperature alternatively. Press CANCEL
button for 3sec to stop the alarm. All stop when he protection is resolved and error code disappears on
the display.
c) In the following circumstances, self-protection starts:
Air inlet or outlet is obstacles;
The heat exchanger is covered with too much dust;
Incorrect power supply (exceeding the range of 220±10%)
Note: When self-protection happens, cut the power supply manually and restart after the error resolved.
2.4.7 Water Temperature Display
a) The temperature on the display is the water temperature in upper part of water tank (over 1/4) which you
will use, but not that of all the water.
b) In water using, the temperature of the lower part may decrease while the upper part still keeps a high
one, and the system will start heating the lower part. And it is normal.
Error Shooting
a) When common error happens, the system enters Standby Mode and could still work, but not so efficient
as normal. Please contact the technician.
b) When serious error happens, the system will be unable to carry on. Please contact the technician.
c) When error happens, the buzzer will buzz in every other minute, the Warning light glitter and the display
indicate the error code and water temperature alternatively. Press CANCEL button for 3sec to stop the
alarm.
2.4.8 Restart after Long Stop
When the system is started after a long time (trial running included), it is normal if the outlet water is unclean.
Keep the tap on and it will be clean soon.
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3. PCB explanation
PCB I/O Ports description
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3.2 SW1/SW2 Setting
3.3 Self-checking function
For the convenience of maintenance and debug, query function is available by Press 2 buttons
together: “ ” + “ ” ” ,then system running parameters will be shown one by one with
following sequence by each pushing of " " or " " button.
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4 Maintenance
4.1 Maintenance
4.1.1 Check the connection between power supply plug and socket and ground wiring regularly;
4.1.2 In some cold area (below 0℃), if the system will be stopped for a long time, all the water should be
released in case of freezing of inner tank and damage of e-heater.
4.1.3 It is recommended to clean the inner tank and e-heater regularly to keep an efficient performance.
4.1.4 Check the sacrificial anode every half year and change it if it has been used out. For more details,
please contact the supplier or the after-sale service.
4.1.5 It is recommended to set a lower temperature to decrease the heat release, prevent scale and
save energy if the outlet water is sufficient.
4.1.6 Clean the air filter every month in case of any effect on the heating performance.
4.1.7 Before shutting the system down for a long time, please: Shut down the power supply; Release all
the water in water tank and the pipeline and close all the valves; Check the inner components
regularly.
4.2 Non-error Malfunction
4.2.1 3-min Protection With the power supplied, an immediate restart after the shutting down will have
to wait 3 min as to protect the compressor.
4.2.2 If self-protection happens and the system stops, check :
When the power indicator lights up, if the system is forced to run while startup requirement has not
been met; If the air outlet or inlet is jammed or strong wind blows to air outlet.
4.2.3 Defrosting
When it is humid and cold, the condenser may defrost and the water-heating capacity decrease.
And the system will stop heating water and start defrosting and then restart water-heating
4.2.4 During defrosting, the compressor keeps running but reverse to defrosting cycle while fan motor
stops;
4.2.5 The defrosting time varies from 3min to 10min according to the ambient temperature and the
frost.
4.3 Temperature Display
4.3.1 When the system stops, a decrease of the temperature is normal as heat released. When it decreases
to some point, the system will restart automatically;
4.3.2 During water-heating, the displayed water temperature might still decrease or not increase for a period
of time because of the heat exchange of the water. When the whole tank of water has reached the set
temperature, the system will stop automatically.
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5 Malfunctions and Resolutions
Malfunction
Cause
Resolutions
Outlet water is
cold.
The display
is dark.
Bad connection of power supply plug and
socket;
Outlet water is set an a low temperature;
Outlet water temperature controller is
damaged;
Circuit board of indicating indicator is
damaged;
Reconnect the plug;
Set outlet water at a higher temperature;
Contact the technician.
No hot water
from the outlet.
Tap water has been cut away;
Water pressure is too low;
Inlet valve has been closed.
It’ll return to normal after water supplied;
Use it when the pressure is higher;
Open the inlet water valve.
Water leakage
The joints on the pipeline are not
sealed well.
Check and reseal all
the joints.
If the unit occurs any malfunction or error, please shut down the system, turn off the power supply, and
consult your service persons for help.
6 Malfunction Code and Troubleshooting
6.1 Malfunction Code and description
Display
Malfunction Description
Display
Malfunction Description
E0
Error of sensor T5U
P1
System high pressure protection
≥2.76MPa active；
≤2.07Mpa inactive
E1
Error of sensor T5L
P2
High discharge temp. protection
Tp>115℃，Protection active
Tp<90℃，Protection inactive
E2
Tank and Wired Controller communication
error
P3
Compressor abnormally stopped protection
The discharge temperature is not so higher than
evaporator temperature after compressor running a
term.
E4
(T3) Condenser output pipe temperature
sensor error
P4
Compressor overloaded protection (10 sec after
compressor startup, Current checking starts ,
1)only compressor running, if it is >7A , the
compressor will be stopped and protected.)
2)Compressor+ e-heater opened, if it is >IEH+7,the
compressor will be stopped and protected.)
E5
(T4) Outdoor ambient temperature sensor
error
LA
When the ambient temp is out of Heat Pump running
zone [-7～43℃],Heat Pump will stop ,then LA
protection code will appear, and ALARM indicator
flashes if the condition maintain more than 20
hours, Need to switch to Enhanced heating Mode.
E6
(Tp) Comp. discharge Sensor error
E9
Compressor suction temperature sensor TH error
E7
Heat Pump system error
If any of P3/P4/P2/P1 continuously appear 3
times within single heating cycle, system will
consider it as “Heat Pump system error”
Ed
EEPROM chip error
EE
E-heater open-circuit error( IEH(Current difference
E-heater on & e-heater off )<1A)
E8
Electric leakage error
If PCB current induction circuit check the
current difference between L,N >14mA,
system consider it as” electric leakage error”
EF
Clock chip error
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6.2 Troubleshooting
A. E0": Water tank temperature sensor (T5U) error
Display
E0
Method of
malfunction
detection
Check whether T5U temperature sensor cable are connected correctly.
Supposed
Causes
1. Temperature sensor cables don’t connect correctly.
2. The sensor terminal is loose.
3. The sensor circuit is short or open
4. The main control board's clamp diodes are short or open.
Troubleshooting
E0
Is T5U port on PCB
loose?
Temperature
sensor is short or
defective.
The chip's pins do not match
correctly or the chip is
defective.
Insert the chip correctly or replace it with
a fine one
Replace the temperature
sensor
Replace the main
control board.
YES
NO
YES
NO
Fasten the port.
YES
NO
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B. E1": Water tank temperature sensor (T5L) error
Display
E1
Method of
malfunction
detection
Check whether T5L temperature sensor cable are connected correctly.
Supposed
Causes
1. Temperature sensor cables don’t connect correctly.
2. The sensor terminal is loose.
3. The sensor circuit is short or open
4. The main control board's clamp diodes are short or open.
Troubleshooting
E1
Is T5L port on PCB
loose?
Temperature
sensor is short or
defective.
The chip's pins do not match
correctly or the chip is
defective.
Insert the chip correctly or replace it with
a fine one
Replace the temperature
sensor
Replace the main
control board.
YES
NO
YES
NO
Fasten the port.
YES
NO
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C. "E4": The evaporator temperature sensor (T3) error
Display
E4
Method of
malfunction
detection
Check whether T3 temperature sensor cable are connected correctly.
Supposed
Causes
1. Temperature sensor cables don’t connect correctly.
2. The sensor terminal is loose.
3. The sensor circuit is short or open
4. The main control board's clamp diodes are short or open.
Troubleshooting
E4
Is T3 port on PCB loose?
Temperature
sensor is short or
defective.
The chip's pins do not match
correctly or the chip is
defective.
Insert the chip correctly or replace it with
a fine one
Replace the temperature
sensor
Replace the main
control board.
YES
NO
YES
NO
Fasten the port.
YES
NO
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D. "E5": The ambient temperature sensor (T4) error
Display
E5
Method of
malfunction
detection
Check whether T4 temperature sensor cable are connected correctly.
Supposed
Causes
1. Temperature sensor cables don’t connect correctly.
2. The sensor terminal is loose.
3. The sensor circuit is short or open
4. The main control board's clamp diodes are short or open.
Troubleshooting
E5
Is T5 port on PCB loose?
Temperature
sensor is short or
defective.
The chip's pins do not match
correctly or the chip is
defective.
Insert the chip correctly or replace it with
a fine one
Replace the temperature
sensor
Replace the main
control board.
YES
NO
YES
NO
Fasten the port.
YES
NO
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E. "E6": The discharge temperature sensor (Tp) error
Display
E6
Method of
malfunction
detection
Check whether Tp temperature sensor cable are connected correctly.
Supposed
Causes
1. Temperature sensor cables don’t connect correctly.
2. The sensor terminal is loose.
3. The sensor circuit is short or open
4. The main control board's clamp diodes are short or open.
Troubleshooting
E6
Is Tp port on PCB loose?
Temperature sensor is
short or defective.
The chip's pins do not match
correctly or the chip is
defective.
Insert the chip correctly or replace it with
a fine one
Replace the temperature
sensor
Replace the main
control board.
YES
NO
YES
NO
Fasten the port.
YES
NO
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52
F. "E8": Electric leakage protection error
Display
E8
Method of
malfunction
detection
Check whether the power line is damage.
Supposed
Causes
1. The power line doesn’t pass through leakage detection components.
2. The electronic component is leakage.
3. There is some conducting liquid on the main board .
4. The power line is damage.
Troubleshooting
E8
Check whether there is
some conducting liquid
on the main board
Check whether the power
line is damage.
Check whether the power line
pass through the leakage
detection components.
Make the line pass through leakage
detection components.
Replace the electronic
component
Replace the main
control board.
NO
YES
YES
NO
Make the main board dry.
YES
NO
Check electronic component
whether there is leakage.
YES
Replace the power line
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53
G. "E9": The suction temperature sensor (Th) error
Display
E9
Method of
malfunction
detection
Check whether Th temperature sensor cable are connected correctly.
Supposed
Causes
1. Temperature sensor cables don’t connect correctly.
2. The sensor terminal is loose.
3. The sensor circuit is short or open
4. The main control board's clamp diodes are short or open.
Troubleshooting
E9
Is Th port on PCB loose?
Temperature sensor is
short or defective.
The chip's pins do not match
correctly or the chip is
defective. Turn the power on
again, is”E9”displayed?
Insert the chip correctly or replace it with
a fine one
Replace the temperature
sensor
Replace the main
control board.
YES
NO
YES
NO
Fasten the port.
YES
NO
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H. "EE": The E-heater has no current error
Display
EE
Method of
malfunction
detection
Check whether the power line is connected correctly.
Supposed
Causes
1. The power voltage is too low or high
2. The e-heater is broken.
3. The electronic component on the main board for E-heater is broken .
4. The thermostat is open.
Troubleshooting
E8
Check whether the power
voltage is at the range of
220 V±10%
Check whether the
electronic component on
the main board is broken.
Check whether the e-heater
is broken.
Replace the e-heater.
Close the thermostat
Replace the main
control board.
NO
YES
YES
NO
Wait for the voltage normal or use a
voltage regulator
YES
NO
Check whether the thermostat
is open..
YES
Replace the electronic
component
NO
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I. "Ed": EEPROM malfunction
Display
Ed
Method of
malfunction
detection
Check whether EEPROM is normal
Supposed
Causes
1. Something wrong with the outdoor unit PCB.
2. Something wrong with the EEPROM.
3. External factor other than malfunction.
Troubleshooting
Ed
Turn the power supply off
once and then back on
Is normal reset
possible?
Turn the power supply off
and replace the EEPROM,
Problem could be cause by External
factor (noise, etc.) other than
malfunction
Replace the main control
board.
Continue operation
YES
NO
YES
NO
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56
J. "EF": Clock chip error
Display
EF
Method of
malfunction
detection
Check whether the clock chip is damage.
Supposed
Causes
1. The clock chip is damage.
2. There is something wrong in the main board.
Troubleshooting
EF
Check whether the clock
chip is damage.
Continue operation
Power on again. Is “EF”
appear?
Replace the main board.
NO
YES
Replace the clock chip.
YES
NO
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