Daikin FTXA20A User manual

Service manual
Split Stylish R32
FTXA20A(W)(S)(T)
FTXA20B(B)(S)(T)
FTXA25A(W)(S)(T)
FTXA25B(B)(S)(T)
FTXA35A(W)(S)(T)
FTXA35B(B)(S)(T)
FTXA42A(W)(S)(T)
FTXA42B(B)(S)(T)
FTXA50A(W)(S)(T)
FTXA50B(B)(S)(T)
RXA42A
RXA50A
RXA20A(9)
RXA25A(9)
RXA35A(9)
RXA42B
RXA50B

Disclaimer
Service manual
2
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
Disclaimer
The present publication is drawn up by way of information only and does not constitute an offer binding upon
Daikin Europe N.V.. Daikin Europe N.V. has compiled the content of this publication to the best of its knowledge.
No express or implied warranty is given for the completeness, accuracy, reliability or fitness for particular purpose
of its content and the products and services presented therein. Specifications are subject to change without prior
notice. Daikin Europe N.V. explicitly rejects any liability for any direct or indirect damage, in the broadest sense,
arising from or related to the use and/or interpretation of this publication. All content is copyrighted by Daikin
Europe N.V..

Version log
Service manual
3
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
Version log
Version code Description Date
ESIE18-03 Document release October 2018
ESIE18-03B See below June 2019
The following updates have been applied to the Service Manual:
•Outdoor unit models RXA42B and RXA50B added.
•Technical data – Wiring diagram: Wiring diagrams for new models added.
•Technical data – Piping diagram: Piping diagrams for new models added.
•Technical data – Component overview: Component overviews for new models added.
Version code Description Date
ESIE18-03C See below February 2020
The following updates have been applied to the Service Manual:
•Indoor unit models CTXA15B and FTXA20~50B added.
•Outdoor unit fan motor: Checking procedures updated.
•Inverter PCB – Checking procedures: To perform an electrical check of the inverter PCB updated.
Version code Description Date
ESIE18-03D See below May 2021
The following updates have been applied to the Service Manual:
•Outdoor unit models RXA-A9 added.
•Indoor unit models CTXA15A and CTXA15B deleted.
•Technical data – Field settings: To reduce maximum sound levels added.
•Indoor unit main PCB: Checking + repair procedures updated.
•Indoor unit power PCB: Checking + repair procedures added.
•Main PCB: Checking + repair procedures updated.
•Reactor: Checking procedures: To perform an electrical check of the reactor updated.

Table of contents
Service manual
4
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
Table of contents
1 Troubleshooting 7
1.1 To display the error code on the user interface ............................................................................................................ 7
1.2 To reset the error code via remote controller ............................................................................................................... 7
1.3 To reset the error code via outdoor unit ....................................................................................................................... 7
1.4 To perform a test run...................................................................................................................................................... 7
1.4.1 To perform a test run using the user interface ............................................................................................. 8
1.5 Error based troubleshooting........................................................................................................................................... 8
1.5.1 A1-00 – PCB abnormality ............................................................................................................................... 8
1.5.2 A5-00 – Outdoor unit: High pressure peak cut / freeze protection problem ............................................... 9
1.5.3 A6-00 – Indoor unit fan motor abnormality .................................................................................................. 9
1.5.4 AH-00 – Streamer unit abnormality............................................................................................................... 10
1.5.5 C4-00 – Heat exchanger temperature sensor problem................................................................................. 10
1.5.6 C9-00 – Room thermistor abnormality.......................................................................................................... 11
1.5.7 CC-00 – Humidity sensor abnormality ........................................................................................................... 11
1.5.8 CE-00 – Intelligent thermal sensor abnormality............................................................................................ 12
1.5.9 E1-00 – Outdoor unit: PCB defect.................................................................................................................. 12
1.5.10 E3-00 – Outdoor unit: Actuation of high pressure switch............................................................................. 13
1.5.11 E5-00 – Outdoor unit: Overheat of inverter compressor motor................................................................... 14
1.5.12 E6-00 – Outdoor unit: Compressor startup defect........................................................................................ 15
1.5.13 E7-00 – Outdoor unit: Malfunction of outdoor unit fan motor .................................................................... 16
1.5.14 E8-00 – Outdoor unit: Power input overvoltage ........................................................................................... 16
1.5.15 EA-00 – Outdoor unit: Cool/heat switchover problem ................................................................................. 17
1.5.16 F3-00 – Outdoor unit: Malfunction of discharge pipe temperature............................................................. 18
1.5.17 F6-00 – Outdoor unit: Abnormal high pressure in cooling............................................................................ 19
1.5.18 F8-00 – System shutdown due to compressor internal temperature abnormality...................................... 20
1.5.19 H0-00 – Outdoor unit: Voltage/current sensor problem .............................................................................. 20
1.5.20 H3-00 – Outdoor unit: Malfunction of high pressure switch ........................................................................ 21
1.5.21 H6-00 – Outdoor unit: Malfunction of position detection sensor ................................................................ 22
1.5.22 H8-00 – Outdoor unit: Malfunction of compressor input system................................................................. 23
1.5.23 H9-00 – Outdoor unit: Malfunction of outdoor air thermistor ..................................................................... 23
1.5.24 J3-00 – Outdoor unit: Malfunction of discharge pipe thermistor................................................................. 24
1.5.25 J6-00 – Outdoor unit: Malfunction of heat exchanger thermistor ............................................................... 24
1.5.26 L3-00 – Outdoor unit: Electrical box temperature rise problem................................................................... 24
1.5.27 L4-00 – Outdoor unit: Malfunction of inverter radiating fin temperature rise ............................................ 25
1.5.28 L5-00 – Outdoor unit: Inverter instantaneous overcurrent .......................................................................... 26
1.5.29 P4-00 – Outdoor unit: Malfunction of radiating fin temperature sensor ..................................................... 27
1.5.30 U0-00 – Outdoor unit: Shortage of refrigerant ............................................................................................. 27
1.5.31 U2-00 – Outdoor unit: Defect of power supply voltage ................................................................................ 28
1.5.32 U4-00 – Indoor/outdoor unit communication problem................................................................................ 29
1.5.33 U5-00 – User interface communication problem.......................................................................................... 30
1.5.34 UA-00 – Indoor unit, outdoor unit mismatching problem ............................................................................ 30
1.6 Symptom based troubleshooting ................................................................................................................................... 32
1.6.1 Operation does not start................................................................................................................................ 32
1.6.2 Operation sometimes stops ........................................................................................................................... 32
1.6.3 Operation starts but the unit does not cool/heat ......................................................................................... 33
1.6.4 Operating noise and vibrations...................................................................................................................... 34
1.6.5 Abnormal high pressure ................................................................................................................................. 35
1.6.6 Abnormal low pressure .................................................................................................................................. 36
1.6.7 Indoor fan starts operating but the compressor does not operate.............................................................. 37
1.6.8 Operation starts and the unit stops immediately.......................................................................................... 38
1.6.9 Operation stops, unit cannot start for a while .............................................................................................. 38
1.6.10 Unit discharges white mist ............................................................................................................................. 39
1.6.11 Humidifying problem...................................................................................................................................... 39
1.6.12 Swing flap does not operate .......................................................................................................................... 39
2 Components 40
2.1 4-way valve...................................................................................................................................................................... 40
2.1.1 Checking procedures...................................................................................................................................... 40
2.1.2 Repair procedures .......................................................................................................................................... 43
2.2 Compressor ..................................................................................................................................................................... 46
2.2.1 Checking procedures...................................................................................................................................... 46
2.2.2 Repair procedures .......................................................................................................................................... 52
2.3 Expansion valve............................................................................................................................................................... 57
2.3.1 Checking procedures...................................................................................................................................... 57
2.3.2 Repair procedures .......................................................................................................................................... 60

Table of contents
Service manual
5
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
2.4 Front panel motor........................................................................................................................................................... 65
2.4.1 Checking procedures...................................................................................................................................... 65
2.4.2 Repair procedures .......................................................................................................................................... 66
2.5 High pressure switch....................................................................................................................................................... 67
2.5.1 Checking procedures...................................................................................................................................... 67
2.5.2 Repair procedures .......................................................................................................................................... 69
2.6 Humidity sensor .............................................................................................................................................................. 70
2.6.1 Checking procedures...................................................................................................................................... 70
2.6.2 Repair procedures .......................................................................................................................................... 71
2.7 Indoor unit fan motor ..................................................................................................................................................... 73
2.7.1 Checking procedures...................................................................................................................................... 73
2.7.2 Repair procedures .......................................................................................................................................... 73
2.8 Indoor unit main PCB...................................................................................................................................................... 75
2.8.1 Checking procedures...................................................................................................................................... 75
2.8.2 Repair procedures .......................................................................................................................................... 78
2.9 Indoor unit power PCB.................................................................................................................................................... 81
2.9.1 Checking procedures...................................................................................................................................... 81
2.9.2 Repair procedures .......................................................................................................................................... 84
2.10 Intelligent thermal sensor............................................................................................................................................... 88
2.10.1 Checking procedures...................................................................................................................................... 88
2.10.2 Repair procedures .......................................................................................................................................... 88
2.11 Inverter PCB .................................................................................................................................................................... 89
2.11.1 Checking procedures...................................................................................................................................... 89
2.11.2 Repair procedures .......................................................................................................................................... 91
2.12 Main PCB ......................................................................................................................................................................... 91
2.12.1 Class 20~35 units............................................................................................................................................ 91
2.12.2 Class 42~50 units............................................................................................................................................ 99
2.13 Outdoor unit fan motor .................................................................................................................................................. 111
2.13.1 RXA20~35A3+5 units ...................................................................................................................................... 111
2.13.2 RXA20~35A2 + class 42~50 units ................................................................................................................... 115
2.14 Plate work ....................................................................................................................................................................... 120
2.14.1 Outdoor unit ................................................................................................................................................... 120
2.14.2 Indoor unit ...................................................................................................................................................... 126
2.15 Reactor ............................................................................................................................................................................ 132
2.15.1 Checking procedures...................................................................................................................................... 132
2.15.2 Repair procedures .......................................................................................................................................... 136
2.16 Streamer unit .................................................................................................................................................................. 137
2.16.1 Checking procedures...................................................................................................................................... 137
2.16.2 Repair procedures .......................................................................................................................................... 137
2.17 Swing flap motor............................................................................................................................................................. 138
2.17.1 Main swing flap motor ................................................................................................................................... 138
2.17.2 Secondary swing flap motor........................................................................................................................... 140
2.18 Swing raster motor ......................................................................................................................................................... 143
2.18.1 Checking procedures...................................................................................................................................... 143
2.18.2 Repair procedures .......................................................................................................................................... 144
2.19 Thermistors ..................................................................................................................................................................... 144
2.19.1 Refrigerant side thermistors .......................................................................................................................... 144
2.19.2 Other thermistors........................................................................................................................................... 151
2.20 Wifi control PCB .............................................................................................................................................................. 153
2.20.1 Checking procedures...................................................................................................................................... 153
2.20.2 Repair procedures .......................................................................................................................................... 154
3 Third party components 156
3.1 Electrical circuit............................................................................................................................................................... 156
3.1.1 Checking procedures...................................................................................................................................... 156
3.1.2 Repair procedures .......................................................................................................................................... 157
3.2 Refrigerant circuit ........................................................................................................................................................... 158
3.2.1 Checking procedures...................................................................................................................................... 158
3.2.2 Repair procedures .......................................................................................................................................... 162
3.3 External factors ............................................................................................................................................................... 165
3.3.1 Checking procedures...................................................................................................................................... 165
4 Maintenance 167
4.1 To clean the outdoor unit heat exchanger..................................................................................................................... 167
4.2 To clean the indoor unit heat exchanger ....................................................................................................................... 167
4.3 To clean the indoor unit heat exchanger in extreme condition .................................................................................... 167
4.4 To clean the air filters ..................................................................................................................................................... 168
5 Technical data 170
5.1 Detailed information setting mode ................................................................................................................................ 170

Table of contents
Service manual
6
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
5.1.1 Detailed information setting mode: Indoor unit ........................................................................................... 170
5.1.2 Detailed information setting mode: Outdoor unit ........................................................................................ 170
5.1.3 Detailed information setting mode: Remote controller................................................................................ 170
5.2 Wiring diagram................................................................................................................................................................ 171
5.2.1 Wiring diagram: Indoor unit........................................................................................................................... 171
5.2.2 Wiring diagram: Outdoor unit........................................................................................................................ 173
5.3 Piping diagram ................................................................................................................................................................ 176
5.3.1 Piping diagram: Indoor unit............................................................................................................................ 176
5.3.2 Piping diagram: Outdoor unit......................................................................................................................... 177
5.4 Component overview...................................................................................................................................................... 180
5.4.1 Component overview: Indoor unit................................................................................................................. 180
5.4.2 Component overview: Outdoor unit.............................................................................................................. 182
5.5 Field information report ................................................................................................................................................. 185
5.6 Service tools .................................................................................................................................................................... 188
5.7 Field settings ................................................................................................................................................................... 189
5.7.1 To control heating only mode........................................................................................................................ 189
5.7.2 To adjust target set temperature in heating operation ................................................................................ 189
5.7.3 To control the indoor unit fan during thermostat off in cooling................................................................... 190
5.7.4 To change auto restart ON to OFF ................................................................................................................. 190
5.7.5 To control cooling mode only ........................................................................................................................ 190
5.7.6 To reduce maximum sound levels ................................................................................................................. 191

1 | Troubleshooting
Service manual
7
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
1 Troubleshooting
1.1 To display the error code on the user interface
1Hold for about 5seconds.
Result: blinks in the temperature display section.
2Press repeatedly until a continuous beep is heard.
Result: The code is now displayed on the display.
INFORMATION
▪A short beep and 2 consecutive beeps indicate non-corresponding codes.
▪To cancel the code display, hold for 5 seconds. The code will also
disappear from the display if the button is NOT pressed within 1minute.
1.2 To reset the error code via remote controller
Prerequisite: Problem is solved.
1Press the ON/OFF button of the remote controller to reset the error.
1.3 To reset the error code via outdoor unit
Prerequisite: Problem is solved.
1Perform a power reset to reset the error code.
1.4 To perform a test run
Prerequisite: Power supply MUST be in the specified range.
Prerequisite: Test run may be performed in cooling or heating mode.
Prerequisite: Test run should be performed in accordance with the operation
manual of the indoor unit to make sure that all functions and parts are working
properly.
1In cooling mode, select the lowest programmable temperature. In heating
mode, select the highest programmable temperature. Test run can be
disabled if necessary.
2When the test run is finished, set the temperature to a normal level. In cooling
mode: 26~28°C, in heating mode: 20~24°C.
3The system stops operating 3minutes after the unit is turned OFF.
INFORMATION
▪Even if the unit is turned OFF, it consumes electricity.
▪When the power turns back on after a power break, the previously selected
mode will be resumed.

1 | Troubleshooting
Service manual
8
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
1.4.1 To perform a test run using the user interface
1Press to switch the system on.
2Press and simultaneously.
3Press , select and press .
Result: Test run operation will stop automatically after about 30minutes.
4To stop operation sooner, press .
1.5 Error based troubleshooting
1.5.1 A1-00 – PCB abnormality
Trigger Effect Reset
The system CANNOT set
the internal settings.
Unit will stop operating. Power reset via outdoor
unit.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Check for improper combination of the indoor unit and the outdoor unit. See
the combination table in the Databook for more information.
2Perform a check of the power supply, connections, wiring,… between the
outdoor unit and the indoor unit. See "3.1Electrical circuit"[4156].
Possible cause: Faulty wiring between the outdoor unit and the indoor unit.
3Check if the power supply is conform with the regulations. See "3.1Electrical
circuit"[4156].
Possible cause:
▪Faulty or disturbance of the power supply (imbalance >4%),
▪Power drop,
▪Short circuit.
4Perform a check of the indoor unit main PCB. See "2.8 Indoor unit main
PCB"[475].
Possible cause: Faulty indoor unit main PCB.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.

1 | Troubleshooting
Service manual
9
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
1.5.2 A5-00 – Outdoor unit: High pressure peak cut / freeze protection problem
Trigger Effect Reset
During cooling operation,
indoor heat exchanger
temperature is below 0°C
(freeze‑up protection
control).
Unit will stop operating. Automatic reset when
temperature is within
range.
During heating operation,
indoor heat exchanger
temperature is above
65°C (heating peak‑cut
control).
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Check for objects near the indoor unit that may block the airflow. See
"3.3External factors"[4165].
Possible cause: Airflow of the indoor unit is blocked.
2Clean the air filter of the indoor unit(s). See "4Maintenance"[4167].
Possible cause: Faulty or dirty air filter.
3Clean the indoor unit heat exchanger. See "4Maintenance"[4167].
Possible cause: Dirty indoor unit heat exchanger.
4Perform a check of the indoor unit heat exchanger thermistor. See
"2.19Thermistors"[4144].
Possible cause: Faulty indoor unit heat exchanger thermistor.
5Perform a check of the indoor unit main PCB. See "2.8 Indoor unit main
PCB"[475].
Possible cause: Faulty indoor unit main PCB.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
1.5.3 A6-00 – Indoor unit fan motor abnormality
Trigger Effect Reset
The rotation speed of the
fan motor is NOT
detected while the output
voltage to the fan is at its
maximum.
Unit will stop operating. Power reset via the
outdoor unit.

1 | Troubleshooting
Service manual
10
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Perform a check of the indoor unit main PCB. See "2.8 Indoor unit main
PCB"[475].
Possible cause: Faulty indoor unit main PCB.
2Perform a check of the indoor unit fan motor. See "2.7 Indoor unit fan
motor"[473].
Possible cause: Faulty indoor unit fan motor.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
1.5.4 AH-00 – Streamer unit abnormality
Trigger Effect Reset
Streamer unit starts
electric discharge when
operation starts after
approximately 90 to
180seconds.
Unit will NOT stop
operating.
Manual reset via user
interface.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Perform a check of the streamer unit. See "2.16Streamer unit"[4137].
Possible cause: Faulty streamer unit.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
1.5.5 C4-00 – Heat exchanger temperature sensor problem
Trigger Effect Reset
Refrigerant liquid
thermistor detects an
open or short circuit
during compressor
operation.
Unit will stop operating. Power reset.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.

1 | Troubleshooting
Service manual
11
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
1Perform a check of the indoor unit heat exchanger thermistor. See
"2.19Thermistors"[4144].
Possible cause: Faulty indoor unit heat exchanger thermistor.
2Perform a check of the indoor unit main PCB. See "2.8 Indoor unit main
PCB"[475].
Possible cause: Faulty indoor unit main PCB.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
1.5.6 C9-00 – Room thermistor abnormality
Trigger Effect Reset
Resistance value is out of
range. Temperature
measured <–43.6°C or
>90°C.
Unit will stop operating. Automatic reset when
resistance is within range.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Perform a check of the indoor unit air (room) thermistor. See
"2.19Thermistors"[4144].
Possible cause: Faulty indoor unit air (room) thermistor.
2Perform a check of the indoor unit main PCB. See "2.8 Indoor unit main
PCB"[475].
Possible cause: Faulty indoor unit main PCB.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
1.5.7 CC-00 – Humidity sensor abnormality
Trigger Effect Reset
▪Disconnected sensor
▪Broken sensor
▪Communication error
Unit will stop operating. Manual reset via user
interface.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Perform a check of the humidity sensor. See "2.6Humidity sensor"[470].
Possible cause: Faulty humidity sensor.

1 | Troubleshooting
Service manual
12
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
1.5.8 CE-00 – Intelligent thermal sensor abnormality
Trigger Effect Reset
▪Disconnected sensor
▪Broken sensor
▪Communication error
Unit will stop operating. Manual reset via user
interface.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Perform a check of the intelligent thermal sensor. See "2.10 Intelligent
thermal sensor"[488].
Possible cause: Faulty intelligent thermal sensor.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
1.5.9 E1-00 – Outdoor unit: PCB defect
Trigger Effect Reset
Main PCB detects that
EEPROM is abnormal.
Unit will stop operating. Manual reset via user
interface.
Power reset.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Perform a check of the main PCB. See "2.12Main PCB"[491].
Possible cause: Faulty main PCB.
2Check if the power supply is conform with the regulations. See "3.1Electrical
circuit"[4156].
Possible cause:
▪Faulty or disturbance of the power supply (imbalance >4%),
▪Power drop,
▪Short circuit.
3Perform a check of the outdoor unit fan motor. See "2.13 Outdoor unit fan
motor"[4111].
Possible cause: Faulty outdoor unit fan motor.
4Perform a check of the compressor. See "2.2Compressor"[446].

1 | Troubleshooting
Service manual
13
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
Possible cause: Faulty compressor or miswiring of the compressor power
supply cable.
Prerequisite: Stop the unit operation via the user interface.
5Turn OFF the respective circuit breaker.
DANGER: RISK OF ELECTROCUTION
Wait for at least 10 minutes after the circuit breaker has been turned OFF, to be sure
the rectifier voltage is below 10VDC before proceeding.
6Check that the thermal interface grease is applied properly on the (PCB or
refrigerant piping) contact surface of the heat sink. Adjust if needed.
Possible cause: Thermal interface grease NOT applied properly on the heat
sink.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
1.5.10 E3-00 – Outdoor unit: Actuation of high pressure switch
Trigger Effect Reset
High pressure switch
opens due to measured
pressure above high
pressure switch operating
point.
Unit will stop operating. Manual reset via user
interface.
High pressure control
(measured pressure just
below high pressure
switch operating point)
occurs 16 times within
300minutes.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Check that all stop valves of the refrigerant circuit are open. See
"3.2Refrigerant circuit"[4158].
Possible cause: Closed stop valve in the refrigerant circuit.
2Perform a check of the high pressure switch. See "2.5 High pressure
switch"[467].
Possible cause: Faulty high pressure switch.
3Perform a check of the main PCB. See "2.12Main PCB"[491].
Possible cause: Faulty main PCB.
4Check if the refrigerant circuit is correctly charged. See "3.2 Refrigerant
circuit"[4158].
Possible cause: Refrigerant overcharge.

1 | Troubleshooting
Service manual
14
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
5Check for the presence of non‑condensables and/or humidity in the
refrigerant circuit. See "3.2Refrigerant circuit"[4158].
Possible cause: Non‑condensables and/or humidity in the refrigerant circuit.
6Check if the refrigerant circuit is clogged. See "3.2Refrigerant circuit"[4158].
Possible cause: Clogged refrigerant circuit.
7Perform a check of the outdoor unit fan motor. See "2.13 Outdoor unit fan
motor"[4111].
Possible cause: Faulty outdoor unit fan motor.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
1.5.11 E5-00 – Outdoor unit: Overheat of inverter compressor motor
Trigger Effect Reset
Compressor overload is
detected.
Unit will NOT stop
operating.
Automatic reset if the unit
runs without warning for
60seconds.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Check that all stop valves of the refrigerant circuit are open. See
"3.2Refrigerant circuit"[4158].
Possible cause: Closed stop valve in the refrigerant circuit.
2Perform a check of the discharge pipe thermistor. See
"2.19Thermistors"[4144].
Possible cause: Faulty discharge pipe thermistor or connector fault.
3Perform a check of the outdoor unit fan motor. See "2.13 Outdoor unit fan
motor"[4111].
Possible cause: Faulty outdoor unit fan motor.
4Perform a check of the compressor. See "2.2Compressor"[446].
Possible cause: Faulty compressor or miswiring of the compressor power
supply cable.
5Perform a check of the expansion valve. See "2.3Expansion valve"[457].
Possible cause: Faulty expansion valve.
6Perform a check of the 4‑way valve. See "2.14-way valve"[440].
Possible cause: Faulty 4‑way valve.
7Perform a check of the main PCB. See "2.12Main PCB"[491].
Possible cause: Faulty main PCB.
8Check if the refrigerant circuit is correctly charged. See "3.2 Refrigerant
circuit"[4158].
Possible cause: Refrigerant shortage.

1 | Troubleshooting
Service manual
15
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
9Check for the presence of non‑condensables and/or humidity in the
refrigerant circuit. See "3.2Refrigerant circuit"[4158].
Possible cause: Non‑condensables and/or humidity in the refrigerant circuit.
10 Check if the refrigerant circuit is clogged. See "3.2Refrigerant circuit"[4158].
Possible cause: Clogged refrigerant circuit.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
1.5.12 E6-00 – Outdoor unit: Compressor startup defect
Trigger Effect Reset
The motor rotor does
NOT rotate when the
compressor is energized.
Unit will NOT stop
operating.
Automatic reset after a
continuous run for
10minutes.
Unit will stop operating Manual reset via user
interface.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Perform a check of the discharge pipe thermistor. See
"2.19Thermistors"[4144].
Possible cause: Faulty discharge pipe thermistor or connector fault.
2Check that all stop valves of the refrigerant circuit are open. See
"3.2Refrigerant circuit"[4158].
Possible cause: Closed stop valve in the refrigerant circuit.
3Check if the refrigerant circuit is clogged. See "3.2Refrigerant circuit"[4158].
Possible cause: Clogged refrigerant circuit.
4Check if the refrigerant circuit is correctly charged. See "3.2 Refrigerant
circuit"[4158].
Possible cause: Refrigerant overcharge or shortage.
5Check for the presence of non‑condensables and/or humidity in the
refrigerant circuit. See "3.2Refrigerant circuit"[4158].
Possible cause: Non‑condensables and/or humidity in the refrigerant circuit.
6Perform a check of the compressor. See "2.2Compressor"[446].
Possible cause: Faulty compressor or miswiring of the compressor power
supply cable.
7Perform a check of the main PCB. See "2.12Main PCB"[491].
Possible cause: Faulty main PCB.
8Perform a check of the 4‑way valve. See "2.14-way valve"[440].
Possible cause: Faulty 4‑way valve.
9Perform a check of the expansion valve. See "2.3Expansion valve"[457].

1 | Troubleshooting
Service manual
16
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
Possible cause: Faulty expansion valve.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
1.5.13 E7-00 – Outdoor unit: Malfunction of outdoor unit fan motor
Trigger Effect Reset
Fan does NOT start
15~30seconds after ON
signal.
It can occur that the error
code is triggered when
the fan motor is running
caused by a faulty
rotating sensor signal.
Unit will stop operating. Manual reset via user
interface.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Perform a check of the outdoor unit fan motor. See "2.13 Outdoor unit fan
motor"[4111].
Possible cause: Faulty outdoor unit fan motor.
2Perform a check of the main PCB. See "2.12Main PCB"[491].
Possible cause: Faulty main PCB.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
1.5.14 E8-00 – Outdoor unit: Power input overvoltage
Trigger Effect Reset
Compressor running
current exceeds standard
value for 2.5seconds.
Unit will stop operating. Manual reset via user
interface.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Check the outdoor temperature. See "3.3External factors"[4165].
Possible cause: Outdoor temperature is out of operation range.
2Perform a check of the compressor. See "2.2Compressor"[446].

1 | Troubleshooting
Service manual
17
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
Possible cause: Faulty compressor or miswiring of the compressor power
supply cable.
3Perform a check of the main PCB. See "2.12Main PCB"[491].
Possible cause: Faulty main PCB.
4Check if the power supply is conform with the regulations. See "3.1Electrical
circuit"[4156].
Possible cause:
▪Faulty or disturbance of the power supply (imbalance >4%),
▪Power drop,
▪Short circuit.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
1.5.15 EA-00 – Outdoor unit: Cool/heat switchover problem
Trigger Effect Reset
Room thermistor is NOT
functioning within
operation range.
Unit will NOT stop
operating.
Automatic reset after a
continuous operation for
some time.
If the error occurs too
soon: unit will stop
operating.
Manual reset via user
interface.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Perform a check of the 4‑way valve. See "2.14-way valve"[440].
Possible cause: Faulty 4‑way valve.
2Perform a check of the main PCB. See "2.12Main PCB"[491].
Possible cause: Faulty main PCB.
3Perform a check of the indoor unit air (room) thermistor. See
"2.19Thermistors"[4144].
Possible cause: Faulty indoor unit air (room) thermistor.
4Perform a check of the indoor unit main PCB. See "2.8 Indoor unit main
PCB"[475].
Possible cause: Faulty indoor unit main PCB.
5Check that all stop valves of the refrigerant circuit are open. See
"3.2Refrigerant circuit"[4158].
Possible cause: Closed stop valve in the refrigerant circuit.
6Check if the refrigerant circuit is clogged. See "3.2Refrigerant circuit"[4158].
Possible cause: Clogged refrigerant circuit.
7Check if the refrigerant circuit is correctly charged. See "3.2 Refrigerant
circuit"[4158].

1 | Troubleshooting
Service manual
18
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
Possible cause: Refrigerant overcharge or shortage.
8Check for the presence of non‑condensables and/or humidity in the
refrigerant circuit. See "3.2Refrigerant circuit"[4158].
Possible cause: Non‑condensables and/or humidity in the refrigerant circuit.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
1.5.16 F3-00 – Outdoor unit: Malfunction of discharge pipe temperature
Trigger Effect Reset
Discharge pipe thermistor
detects a too high
temperature.
Unit will NOT stop
operating.
Automatic reset when
temperature drops
normal level.
If the error re-occurs too
soon: unit will stop
operating.
Manual reset via user
interface.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Check that all stop valves of the refrigerant circuit are open. See
"3.2Refrigerant circuit"[4158].
Possible cause: Closed stop valve in the refrigerant circuit.
2Check if the refrigerant circuit is correctly charged. See "3.2 Refrigerant
circuit"[4158].
Possible cause: Refrigerant overcharge or shortage.
3Check for the presence of non‑condensables and/or humidity in the
refrigerant circuit. See "3.2Refrigerant circuit"[4158].
Possible cause: Non‑condensables and/or humidity in the refrigerant circuit.
4Check if the refrigerant circuit is clogged. See "3.2Refrigerant circuit"[4158].
Possible cause: Clogged refrigerant circuit.
5Perform a check of the 4‑way valve. See "2.14-way valve"[440].
Possible cause: Faulty 4‑way valve.
6Perform a check of the expansion valve. See "2.3Expansion valve"[457].
Possible cause: Faulty expansion valve.
7Perform a check of the main PCB. See "2.12Main PCB"[491].
Possible cause: Faulty main PCB.
8Perform a check of all refrigerant side thermistors. See
"2.19Thermistors"[4144].
Possible cause: Faulty refrigerant side thermistor(s).

1 | Troubleshooting
Service manual
19
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
1.5.17 F6-00 – Outdoor unit: Abnormal high pressure in cooling
Trigger Effect Reset
Outdoor heat exchanger
thermistor measures a
too high temperature.
Unit will NOT stop
operating.
Automatic reset when
temperature drops.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Clean the outdoor heat exchanger. See "4Maintenance"[4167].
Possible cause: Dirty outdoor heat exchanger.
2Check that all stop valves of the refrigerant circuit are open. See
"3.2Refrigerant circuit"[4158].
Possible cause: Closed stop valve in the refrigerant circuit.
3Perform a check of the heat exchanger thermistor. See
"2.19Thermistors"[4144].
Possible cause: Faulty heat exchanger thermistor.
4Perform a check of the expansion valve. See "2.3Expansion valve"[457].
Possible cause: Faulty expansion valve.
5Perform a check of the main PCB. See "2.12Main PCB"[491].
Possible cause: Faulty main PCB.
6Check if the refrigerant circuit is correctly charged. See "3.2 Refrigerant
circuit"[4158].
Possible cause: Refrigerant overcharge.
7Check for the presence of non‑condensables and/or humidity in the
refrigerant circuit. See "3.2Refrigerant circuit"[4158].
Possible cause: Non‑condensables and/or humidity in the refrigerant circuit.
8Check if the refrigerant circuit is clogged. See "3.2Refrigerant circuit"[4158].
Possible cause: Clogged refrigerant circuit.
9Perform a check of the outdoor unit fan motor. See "2.13 Outdoor unit fan
motor"[4111].
Possible cause: Faulty outdoor unit fan motor.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.

1 | Troubleshooting
Service manual
20
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
1.5.18 F8-00 – System shutdown due to compressor internal temperature abnormality
Trigger Effect Reset
Temperature discharge
pipe thermistor exceeds
the determined limit.
Unit will stop operating. Manual reset via user
interface.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Check that all stop valves of the refrigerant circuit are open. See
"3.2Refrigerant circuit"[4158].
Possible cause: Closed stop valve in the refrigerant circuit.
2Check if the refrigerant circuit is correctly charged. See "3.2 Refrigerant
circuit"[4158].
Possible cause: Refrigerant overcharge.
3Check for the presence of non‑condensables and/or humidity in the
refrigerant circuit. See "3.2Refrigerant circuit"[4158].
Possible cause: Non‑condensables and/or humidity in the refrigerant circuit.
4Check if the refrigerant circuit is clogged. See "3.2Refrigerant circuit"[4158].
Possible cause: Clogged refrigerant circuit.
5Perform a check of the discharge pipe thermistor. See
"2.19Thermistors"[4144].
Possible cause: Faulty discharge pipe thermistor or connector fault.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
1.5.19 H0-00 – Outdoor unit: Voltage/current sensor problem
Trigger Effect Reset
Compressor voltage (DC)
is out of range before
start‑up.
Unit will stop operating. Manual reset via user
interface.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1Perform a check of the main PCB. See "2.12Main PCB"[491].
Possible cause: Faulty main PCB.
2Check if the power supply is conform with the regulations. See "3.1Electrical
circuit"[4156].