Hokkaido 4 Series User manual

R32
Refrigerant
Wall Type
Air Conditioners
Heat Pump Top Class Models with DC Fan Motor
1 Phase, 220-240V, 50/60Hz Power Supply
Series 4 Models:
HKEU 264 ZAL
HCNI 264 ZA
SERVICE MANUAL [
Release 1.1 ]
HKEU 354 ZAL
HCNI 354 ZA

Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
Table of Contents
Table of Contents
1. PRODUCT DETAILS ............................................................................................................................ 1
2. MODEL REFERENCE ......................................................................................................................... 3
3. DIMENSIONS ..................................................................................................................................... 4
4. ELECTRICAL WIRING DIAGRAMS.................................................................................................... 6
5. OPERATION MODES AND FUNCTIONS........................................................................................... 8
6. TROUBLESHOOTING .......................................................................................................................14
APPENDIX ........................................................................................................................................... 37

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
1. PRODUCT DETAILS
Auto clean (X-fan)
After BLUAIR shut-down, the internal
fan continues to run to favour internal
unit exchanger drying. This function
prevents the formation of mould that
is harmful to the respiratory system.
Autorestart
In case of blackout, the unit resumes
operation with the previously selected
settings once the power supply is
restored.
TOP CLASS DC INVERTER
Wall
RESIDENTIAL R32
24H timer
This function allows users to select
delayed air conditioner on and/or
off within 24 hours, either via remote
(standard) or via Wi-Fi (optional).
Refrigerant
leak detection
Active only in cooling mode, it allows
to identify compressor malfunctions
following the refrigerant leak.
Cold currents
prevention
Through this function in heating
mode, it is possible to avoid the
introduction of cold air into the room
following the defrost cycles.
Anti-freeze function 8° C
In the event of prolonged absence,
a minimum temperature level can be
guaranteed inside the rooms.
By activating the anti-freeze function,
when a temperature lower than
8° C is detected in the room, the
system starts until this temperature is
reached.
Sleep mode
It allows lowering energy consumption
at night. In cooling mode, the system
increases the ambient temperature
within 2 hours, by 2°C (in heating
mode the system lowers the
temperature by 2°C). At the end of 2
hours the fan of the indoor unit works
at low speed. The system keeps the
room temperature constant for the
next 5 hours.
Silence mode
This function allows the operating
speed of the compressor of the
outdoor unit and the fan of the indoor
unit to be reduced to a minimum,
so as to reduce noise and energy
consumption to a minimum.
NEW

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
TOP CLASS DC INVERTER
HKEU 264-354 ZAL
RESIDENTIAL R32
Wall
Models available in 2 power sizes 2.64 ~ 3.52 kW.
Seasonal energy efficiency class in cooling/heating
mode: A+++/A++ (2.64 kW); A++/A++ (3.52 kW).
SEER/SCOP values 8.5/4.6 (2.64 kW).
Operating range in cooling and heating: -15~43°C;
-30~30°C.
Extremely quiet: 21.5 dB(A) (2.64 kW);
22 dB(A) (3.52 kW).
Compact dimensions: only 189 mm deep.
Installation flexibility: up to 25 m splitting length and
10 m height difference between O.U. and I.U.
Possibility of access to tax deductions and to the
thermal account.
"3D" air diffusion
Photocatalytic filter
Position memorization function louvres
(optional)
Main features
Indoor unit model HKEU 264 ZAL HKEU 354 ZAL
Outdoor unit model HCNI 264 ZA HCNI 354 ZA
Type DC-Inverter heat pump
Control Remote control
Rated capacity (T=+35°C)
Cooling
kW 2.64 (0.91~4.40) 3.52 (0.93~4.75)
Rated absorbed power (T=+35°C) kW 0.60 (0.05~1.55) 0.98 (0.05~1.59)
Rated energy eciency coecient EER
3
4.40 3.59
Seasonal energy eciency class 626/2011
1
A+++ A++
Seasonal energy eciency index SEER
2
8.5 8.1
Annual energy consumption kWh/a 111 155
Theoretical load (Pdesignc) kW 2.7 3.5
Rated capacity (T=+7°C)
Heating
kW 2.86 (0.79~6.30) 3.81 (0.98~6.50)
Rated absorbed power (T=+7°C) kW 0.65 (0.14~2.10) 1.026 (0.17~2.13)
Rated energy performance coecient COP
3
4.42 3.71
Energy eciency class (average season) 626/2011
1
A++ A++
Seasonal energy eciency class index (average season) SCOP
2
4.6 4.6
Annual energy consumption kWh/a 792 852
Theoretical load (Pdesignh) kW 2.2 2.8
Operating limits (external temperature) Cooling °C -15~43 -15~43
Heating °C -30~30 -30~30
Electrical data
Power Outdoor unit Ph-V-Hz 1Ph - 220/240V - 50Hz
Power cable Type 3 x 2.5 mm
2
Absorbed current (rated) Cooling A 0.5~7.0 0.5~7.0
Heating A 1.0~9.2 1.2~9.4
Maximum current A 10 10
Maximum absorbed power kW 2.35 2.35
Connection wires between I.U. and O.U. no. 5 5
Refrigerant circuit
Refrigerant (GWP)
4
R32 (675) R32 (675)
Quantity refrigerant pre-load Kg 0.87 0.87
Tons of CO2 equivalent t 0.587 0.587
Diameter of refrigerant piping on liquid/gas mm (inches) ø6.35(1/4”) - ø9.52(3/8”) ø6.35(1/4”) - ø9.52(3/8”)
Max splitting length m 25 25
Max height dierence I.U. /O.U. m 10 10
Split length without additional charge m 5 5
Additional load g/m 12 12
Indoor unit specications
Dimensions LxDxH mm 802x189x297 802x189x297
Net weight Kg 8.5 8.5
Sound pressure level (I.U.) Hi/Mi/Lo/ULo dB(A) 42/35/25/21.5 42/35/25/22
Sound power level (I.U.) Hi dB(A) 56 56
Handled air volume Hi/Mi/Lo m
3
/h 611/479/360 611/479/360
Motor power (Output) W 50 50
Specications of outdoor units
Dimensions LxDxH mm 800x333x554 800x333x554
Net weight Kg 34.7 34.7
Sound pressure level (O.U.) dB(A) 55.5 55.5
Sound power level (O.U.) dB(A) 64 65
Handled air (Max) m
3
/h 2000 2000
Motor power (Output) no. x W 40 40
Optional parts
Wired remote control NO
Centralised control NO
Wi-Fi module KK-WIFI KIT
Infrared
remote
control
1 EU Delegated Regulation No.626/2011 on the new labelling indicating the energy consumption of air conditioners. 2 EU Regulation No.206/2012 - - Value measured according to harmonised standard EN14825. 3 Value measured according to
harmonised standard EN14511. 4 Refrigerant leakage contributes to climate change. When released into the atmosphere, refrigerants with a lower global warming potential (GWP) contribute less to global warming than those with a higher GWP.
This appliance contains a refrigerant with a GWP of 675. If 1 kg of this refrigerant fluid were released into the atmosphere, therefore, the impact on global warming would be 675 times higher than 1 kg of CO2, over a period of 100 years. Under no
circumstances should the user try to intervene on the refrigerant circuit or disassemble the product. Always contact qualified personnel if necessary.

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
2. MODEL REFERENCE
Indoor Unit Model Outdoor Unit Model Capacity(Btu/h) Power Supply
9k
12k
HKEU 264 ZAL HCNI 264 ZA
HKEU 354 ZAL HCNI 354 ZA
Refer to the following table to determine the specific indoor and outdoor unit model number of your pur chased equip-
ment.
220-240V, 50Hz,
1Phase
220-240V, 50Hz,
1Phase

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
3. DIMENSIONS
3.1 Indoor Units
Models HKEU 264 ZAL, HKEU 354 ZAL
Models W (mm) D (mm) H (mm)
HKEU 264 ZAL
HKEU 354 ZAL
802 189 297
802 189 297

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
3.2 Outdoor Units
Models HCNI 264 ZA, HCNI 354 ZA
Unit: mm

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
4. ELECTRICAL WIRING DIAGRAMS
4.1 Indoor Units
Models HKEU 264 ZAL, HKEU 354 ZAL
Abbreviation Paraphrase
Y/G Ground Wire
ION Positive and Negative Ion Generator
CAP Capacitor
PLASMA Electronic Dust Collector
LLIVE
N NEUTRAL
Heater The Electric Heating Belt of Indoor Unit
T1 Indoor Room Temperature
T2 Coil Temperature of Evaporator

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
4.2 Outdoor Units
Models HCNI 264 ZA, HCNI 354 ZA
Abbreviation Paraphrase
4-WAY Gas Valve Assembly/4-WAY VALVE
AC-FAN Alternating Current (AC) FAN
DC-FAN Direct Current (DC) FAN
CT1 AC Current Detector
COMP Compressor
L-PRO Low Pressure Switch
H-PRO High Pressure Switch
T3 Coil Temperature of Condenser
T4 Outdoor Ambient Temperature
TH Compressor Suction Temperature
TP Compressor Discharge Temperature
EEV Electronic Expansion Valve

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
5. OPERATION MODES AND FUNCTIONS
Temperature values abbreviations:
Abbreviation Element
T1 Indoor room temperature
T2 Coil temperature of evaporator
T3 Coil temperature of condenser
T4 Outdoor ambient temperature
TS Set temperature
TP Compressor discharge temperature
5.1 Abbreviation
5.2 Safety Features
Compressor 3-minute delay at restart
Compressor functions are delayed for up to 1 minute upon
the first startup of the unit, and are delayed for up to 3
minutes upon subsequent unit restarts.
Temperature protection of compressor top
The unit will stop working when the compressor top temp.
protector cut off, and will restart after the compressor top
temp. protector restart.
Automatic shut-off based on discharge temperature
If the compressor discharge temperature exceeds 108°C
for 5 seconds, the compressor ceases operation.
Automatic shut-off based on fan speed
If the indoor fan speed registers below 300RPM for an
extended period of time, the unit ceases operation and the
corresponding error code is displayed on the indoor unit.
Inverter module protection
The inverter module has an automatic shut-off mechanism
based on the unit’s current, voltage, and temperature. If
automatic shut-off is initiated, the corresponding error
code is displayed on the indoor unit and the unit ceases
operation.
Indoor fan delayed operation
• When the unit starts, the louver is automatically activated
and the indoor fan will operate after a period of 7 seconds.
• If the unit is in heating mode, the indoor fan is regulated
by the anti-cold wind function.
Compressor preheating
Preheating is automatically activated when T4 sensor is
lower than 3°C.
Sensor redundancy and automatic shut-off
• If one temperature sensor malfunctions, the air conditio-
ner continues operation and displays the corresponding
error code, allowing for emergency use.
• When more than one temperature sensor is malfunctio-
ning, the air conditioner ceases operation.
Refrigerant leakage detection
This function is active only when cooling mode is selec-
ted. It will detect if the compressor is being damaged
by
refrigerant leakage or by compressor overload. This is
measured using the coil temperature of evaporator
T2
when the compressor is in operation.

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
Unit display functions:
Function Display
Temperature. Set temperature value.
Temperature
(fan and Drying
mode).
Room temperature.
Activation of Timer
ON, Fresh, Swing,
Turbo, or Silent. (3s)
Cancellation of
Timer OFF, Fresh,
Swing, Turbo, or
Silent.
(3s)
Defrost.
Warming in heating
mode.
Self-clean (available
on select units only).
Heating in room
temperature
under 8°C.
ECO function
(available on select
units only).
set temperature
gradually illuminates to in
one second interval
5.3 Digital Display
5.4 Fan Mode
When fan mode is activated:
• The outdoor fan and compressor are stopped.
• Temperature control is disabled and no temperature
setting is displayed.
• The indoor fan speed can be set to high, medium, low,
or auto.
• The louver operations are identical to those in cooling
mode.
• Auto fan: In fan-only mode, AC operates the same as
auto fan in cooling mode with the temperature set at
24°C.
5.5 Cooling Mode
5.5.1 Compressor Control
∆T is the programmed parameter of temperature compen-
sation.
• When T1-Ts < ∆T-2°C, the compressor ceases opera-
tion.
• When T1-Ts > ∆T+3°C, the compressor
continues
operation.
• When the AC is operating in mute mode, the
compressor
operates at a low frequency.
• When the current exceeds the preset value, the
current
protection function activates and the compressor
ceases
operation.
5.5.2 Indoor Fan Control
• In cooling mode, the indoor fan operates continuously.
The fan speed can be set to high, medium, low, or auto.
• If the compressor ceases operations when the con-
figured temperature is reached, the indoor fan
motor
operates at the minimum or configured speed.
5.5.3 Outdoor Fan Control
• For 264 and 354 models, the outdoor unit will be run
at
different fan speed according to T4 and
compressor
operating frequency.
• For different outdoor units, the fan speeds are different.
5.5.4 Condenser Temperature Protection
When condenser temperature is more than setting
value,
the compressor will stop.
5.5.5 Evaporator Temperature Protection
When evaporator temperature drops below a
con-
figured value, the compressor and outdoor fan
ceases
operations.
5.6 Heating Mode
5.6.1 Compressor Control
∆T is the programmed parameter of temperature compen-
sation.
• When T1-Ts > -∆T, the compressor ceases operation.
• When T1-TS < -∆T -4.5°C, the compressor
continues
operation.
• When the AC is operating in mute mode, the
compressor
operates at a low frequency.
• When the current exceeds the preset value,
the
current protection function activates and the compres-
sor ceases operation.
fresh defrost run timer

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
∆T Running mode
∆T > 2°C Cooling
-2°C ≤ ∆T ≤ 2°C Fan-only
∆T < -2°C Heating*
5.6.2 Indoor Fan Control
• When the compressor is on, the indoor fan can be set to
high/medium/low/auto.
• When indoor unit coil temperature is low, the anti-cold air
function will start and indoor fan motor will run at low
speed, the speed can’t be changed, when the temperature
is lower than setting value, the indoor fan motor will stop.
• When the indoor temperature reaches the setting tempe-
rature, the compressor will stop, the indoor fan motor will
run at the minimum speed or setting speed. (The anti-cold
air function is valid).
5.6.3 Outdoor Fan Control
• For 264 and 354 models, the outdoor unit will be run at
different fan speed according to T4 and compressor ope-
rating frequency.
• For different outdoor units, the fan speeds are different.
5.6.4 Defrosting mode
For 264 and 354 models:
• The unit enters defrosting mode according to changes in
the temperature value of T3 and T4 as well as the com-
pressor running time.
• In defrosting mode, the compressor continues to run, the
indoor and outdoor motor will cease operation, the defrost
light of the indoor unit will turn on, and the “ ” symbol is
displayed.
• If any one of the following conditions is satisfied, defro-
sting ends and the machine switches to normal heating
mode:
• T3 rises above TCDE1°C.
• T3 maintained above TCDE2°C for 80 seconds.
• Unit runs for 15 minutes consecutively in defrosting
mode.
5.6.5 Evaporator Temperature Protection
When the evaporator temperature exceeds a preset
protection value, the compressor ceases operation.
5.7 Auto-mode
• This mode can be selected with the remote controller．
• In auto mode, the machine selects cooling, heating,
or
fan-only mode on the basis of ∆T (∆T =T1-Ts).
(Heating*: In auto mode, cooling only models run the fan.)
• AC will run in auto mode in the below cases:
• Pressing the forced auto button.
• If AC is off, it will run in auto mode when the timer
on
function is active.
• After setting the mode, AC will run in auto mode if the
compressor keeps not running for certain time.
5.8 Drying mode
• Indoor fan speed is fixed at breeze and can’t be chan-
ged. The louver angle is the same as in cooling mode.
• In drying mode, if room temperature is lower than
10°C,
the compressor will stop and not resume until
room
temperature exceeds 12°C.
• All protections are active and the same as that in
cooling
mode.
5.9 Forced operation function
• Forced cooling mode:
The compressor and outdoor fan continue to run and
the
indoor fan runs at low speed. After running for 30
minutes,
the AC will switch to auto mode with a preset
temperature
of 24°C.
• Forced auto mode:
Forced auto mode operates the same as normal
auto
mode with a preset temperature of 24°C.
• The unit exits forced operation when it receives the
fol-
lowing signals:
• Switch on.
• Switch off.
• Timer on.
• Timer off.
• Changes in:
- Mode.
- Fan speed.
- Sleeping mode.

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
5.10 Auto-Restart function
• The indoor unit has an auto-restart module that allows
the unit to restart automatically. The module automatically
stores the current settings (not including the swing setting)
and, in the case of a sudden power failure, will restore
those settings automatically within 3 minutes after power
returns.
• If the unit was in forced cooling mode, it will run in this
mode for 30 minutes and turns to auto mode with tempera-
ture set to 24°C.
• If there is a power failure while the unit is running, the
compressor starts 3 minutes after the unit restarts. If the
unit was already off before the power failure, the compres-
sor starts 1 minute after the unit restarts.
5.11 Refrigerant Leakage Detection
• With this new technology, the display area will show
“EC” when the outdoor unit detects refrigerant leakage.
• When compressor is active, the value of the Coil tempe-
rature of evaporator T2 has no change or very little
change.
5.12 Louver Position Memory Function
When starting the unit again after shutting down, its louver
will restore to the angle originally set by the user, but the
precondition is that the angle must be within the allowable
range; if it exceeds, it will memorize the maximum angle
of the louver. During operation, if the power fails or the
end user shuts down the unit in the turbo mode, the louver
will restore to the default angle.
5.13 8°C Heating (Optional)
In heating mode, the temperature can be set to as low as
8°C, preventing the indoor area from freezing if unoccu-
pied during severe cold weather.
5.14 Self Clean (Optional)
• If you press “Self Clean” when the unit is in cooling
or
drying mode:
• For cooling only models, the indoor unit will run in
low
fan mode for a certain time, then ceases operation.
• For these heat pump models, the indoor unit will run in
fan-only mode, then low heat, and finally in
fan-only
mode.
• Self Clean keeps the indoor unit dry and prevents
mold
growth.
5.15 Follow Me (Optional)
• If you press “Follow Me” on the remote, the indoor
unit
will beep. This indicates the “Follow Me” function is active.
• Once active, the remote control will send a signal
every
3 minutes, with no beeps. The unit automatically sets
the
temperature according to the measurements from
the
remote control.
• The unit will only change modes if the information
from
the remote control makes it necessary, not from the unit’s
temperature setting.
• If the unit does not receive a signal for 7 minutes or
you
press “Follow Me”, the function turns off. The unit regula-
tes temperature based on its own sensor and settings.
5.16 Silence (Optional)
Press “Silence” on the remote control to enable
the
SILENCE function. While this function is active, the
com-
pressor frequency is maintained at a lower level than
F2.
The indoor unit will run at faint breeze, which
reduces
noise to the lowest possible level.
5.17 Information Inquiry
• To enter information inquiry status, complete the
fol-
lowing procedure within 10 seconds:
• Press LED 3 times.
• Press SWING 3 times.
• If the proceeding is successful, you will hear beeps
for
2 seconds.
• Use the LED and SWING buttons to cycle
through
information displayed.
• Pressing LED will display the next code in the
sequence.
Pressing SWING will show the previous.
• The following table (see next page) shows
information
codes. The screen will display this code for 2
seconds,
then the relevant information for 25 seconds.

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
Displayed Code Explanation Displayed value Meaning Additional Notes
T1
T2
T3
T4
Tb
TP
TH
FT
Fr
Room temp.
-1F,-1E,-1d,-1c,-
1b,-1A
-19—99
A0,A1,…A9
b0,b1,…b9
c0,c1,…c9
d0,d1,…d9
E0,E1,…E9
F0,F1,…F9
-25,-24,-23,-22,
-21,-20
-19—99
100,101,…109
110,111,…119
120,121,…129
130,131,…139
140,141,…149
150,151,…159
Indoor coil temp.
Outdoor coil temp.
Ambient temp.
Outlet temp. of
indoor coil.
Discharge temp.
Suction temp.
Targeted frequency.
Actual frequency.
IF Indoor fan speed.
0
1,2,3,4
14-FF
OFF N/A
OF Outdoor fan speed.
LA EXV opening angle. 0-FF -
CT 0-FF 0-255 minutes.
ST 0-99
1. All displayed temperatures
use actual values.
2. All temperatures are di-
splayed in °C regardless of
remote used.
3. T1, T2, T3, T4, and T2B
display ranges from -25°C to
70°C. TP display ranges
from -20°C to 130 °C.
4. The frequency display ran-
ges from 0 to 159HZ.
5. If the actual values exceed
or fall short of the defined
range, the values closest to
the maximum and minimum
values will be displayed.
Low speed, Medium
speed, High speed,
Turbo.
Actual fan speed is
equal to the display
value converted to de-
cimal value and mul-
tiplied by 10. This is
measured in RPM.
Used for some large capacity
motors.
Used for some small capaci-
ty motors.
The display value is 14-FF
(hexadecimal). Correspond-
ing fan speed ranges from
200RPM to 2550RPM.
Compressor continu-
ous running time.
Causes of compres-
sor stop.
If the actual value exceeds or
falls short of the defined ran-
ge, the value closest to the
maximum and minimum will
be displayed.
Actual EXV opening
value is equal to the
display value conver-
ted to decimal value
and then multiplied
by 2.
For a detailed expla-
nation, contact tech-
nical support.
-

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
Displayed Code Explanation Meaning Additional Notes
A0
Reserved
0-FF
2-28
5-20
5-25
- -
A1
0
1
2
3
4
5
6
L
A
U
T
A
5
T
Displayed Value

- 14 -
Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
6. TROUBLESHOOTING
WARNING
6.1 Safety Caution
Electricity remains in capacitors even when the power supply is off.
Ensure the capacitors are fully discharged before troubleshooting.
• For other models, connect discharge resistance (approx. 100Ω40W) or a soldering iron plug between the positi
-
ve and negative terminals of the electrolytic capacitor.
• The terminals are located on the bottom surface of the outdoor PCB.
Note: This picture is for reference only. Actual appearances may vary.
Discharging position (discharging period is 10 sec. or more)
Plug of soldering iron

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
Operation
Lamp
Timer
Lamp Display Error Information
1 time OFF E0 Indoor unit EEPROM parameter error.
2 times OFF E1 Indoor / outdoor units communication error.
4 times OFF E3 The indoor fan speed is operating outside of the normal range.
5 times OFF E4 Indoor room temperature sensor T1 is in open circuit state or has short
circuit.
6 times OFF E5
Evaporator coil temperature sensor T2 is in open circuit state or has short
circuit.
7 times OFF EC Refrigerant leak detected.
1 time ON F0 Overload current protection.
2 times ON F1 Outdoor ambient temperature sensor T4 is in open circuit state or has
short circuit.
3 times ON F2 Condenser coil temperature sensor T3 is in open circuit state or has
short circuit.
4 times ON F3 Compressor discharge temperature sensor TP is in open circuit state
or has short circuit.
5 times ON F4 Outdoor unit EEPROM parameter error.
6 times ON F5 The outdoor fan speed is operating outside of the normal range.
1 time FLASH p0 IPM malfunction or IGBT over-strong current protection.
2 times FLASH p1 Over voltage or too low voltage protection.
3 times FLASH p2 High temperature protection of IPM module.
5 times FLASH p4 Inverter compressor drive error.
6.2 General Troubleshooting
6.2.1 Error Display (Indoor Unit)
When the indoor unit encounters a recognized error, the indicator light (Operation Lamp) will flash in a
correspon-
ding series, the timer indicator (Timer Lamp) may turn on or begin flashing, and an error code will be displayed.
These error codes are described in the following table.
For other errors:
The display board may show a garbled code or a code undefined by the service manual.
Ensure that this code is not a temperature reading.
Troubleshooting:
Test the unit using the remote control.
If the unit does not respond to the remote, the indoor PCB requires replacement.
If the unit responds, the display board requires replacement.

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
WARNING
Be sure to turn off unit before any maintenance to prevent damage or injury.
No. Problem
1Unit will not start.
2The power switch is on but fans will not start.
3The temperature on the display board cannot be set.
4Unit is on, but the wind is not cold (hot).
5Unit runs, but it shortly stops.
6The unit starts up and stops frequently.
7Unit runs continuously but with insufficient cooling (heating) effect.
8Cooling mode cannot be changed to heating mode.
9Unit is noisy.
6.3 Error Diagnosis and Troubleshooting Without Error Code
6.3.1 Remote maintenance
SUGGESTION:
When troubles occur, please check the following points with Customers before field maintenance.

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
1.Remote Maintenance
Possible causes of trouble
Power failure The main power tripped Loose connecons Faulty transformer The voltage is too high or too low The remote control is powered off Broken remote control
Dirty air filter
Dirty condenser fins The seng temperature is higher/lower than the room's (cooling/heang) The ambient temperature is too high/low when the mode is cooling/heang Fan mode SILENCE funcon is acvated (oponal funcon) Frosng and defrosng frequently
Unit will not start ƿƿƿƿ
The power switch is on but fans will not start ƿƿƿ
The temperature on the display board cannot be set ƿ ƿ
Unit is on but the wind is not cold (hot) ƿ ƿ ƿ
Unit runs, but shortly stops ƿ ƿ ƿ
The unit starts up and stops frequently ƿ ƿ ƿ
Unit runs connuously but insufficient cooling (heang) ƿ ƿ ƿ ƿ ƿ
Cool can not change to heat
Unit is noisy
Test method / remedy
Test voltage Close the power switch Inspect connecons - ghten Change the transformer Test voltage Replace the baery of the remote control Replace the remote control Clean or replace Clean Adjust the seng temperature Turn the AC later
Adjust to cool mode Turn off SILENCE funcon. Turn the AC later
Refrigerant CircuitElectrical Circuit

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Series 4 Models: “Wall” Type Top Class R32 Refrigerant AC
1.Remote Maintenance
Possible causes of trouble
Heavy load condion
Loosen hold down bolts and / or screws
Bad airproof
The air inlet or outlet of either unit is blocked
Interference from cell phone towers and remote boosters
Shipping plates remain aached
Unit will not start
The power switch is on but fans will not start ƿ
The temperature on the display board cannot be set
Unit is on but the wind is not cold (hot)
Unit runs, but shortly stops
The unit starts up and stops frequently ƿ
Unit runs connuously but insufficient cooling (heang) ƿ ƿ ƿ
Cool can not change to heat
Unit is noisy ƿ ƿ
Test method / remedy
Check heat load
Tighten bolts or screws Close all the windows and doors Remove the obstacles
Reconnect the power or press ON/OFF buon on remote control to restart operaon Remove them
Others