Mitsubishi Heavy Industries KX6 series User manual

(OUTDOOR UNIT)
KX6 series
FDC224KXE6, 280KXE6, 335KXE6
FDC224KXE6M, 280KXE6M, 335KXE6M
FDCS224KXE6M, 280KXE6M, 335KXE6M (Corrosin Protection Treatment series)
(Heat pump type)
Manual No. '10
• KX-SM-148
SERVICE MANUAL
Regarding the Duct Connected-High static Pressure-type Outdoor Air Processing Unit
Series (FDU500〜1800FKXE6D), refer to the DATA BOOK No.'10 •KX-DB-144
• Note:
VRF INVERTER MULTI-SYSTEM AIR CONDITIONERS
Alternative refrigerant R410A use models
FDT28KXE6D
FDT36KXE6D
FDT45KXE6D
FDT56KXE6D
FDT71KXE6D
FDT90KXE6D
FDT112KXE6D
FDT140KXE6D
FDT160KXE6D
FDTC22KXE6D
FDTC28KXE6D
FDTC36KXE6D
FDTC45KXE6D
FDTC56KXE6D
FDU224KXE6D
FDU280KXE6D
FDTW28KXE6D
FDTW45KXE6D
FDTW56KXE6D
FDTS45KXE6D
FDTS71KXE6D
FDTQ22KXE6D
FDTQ28KXE6D
FDTQ36KXE6D
(INDOOR UNIT) - KX6 series -
FDFW28KXE6D
FDFW45KXE6D
FDFW56KXE6D
FDU500FKXE6D
FDU850FKXE6D
FDU1300FKXE6D
FDU1800FKXE6D
FDUM22KXE6D
FDUM28KXE6D
FDUM36KXE6D
FDUM45KXE6D
FDUM56KXE6D
FDUM71KXE6D
FDUM90KXE6D
FDUM112KXE6D
FDUM140KXE6D
FDUT22KXE6D
FDUT28KXE6D
FDUT36KXE6D
FDUT45KXE6D
FDUT56KXE6D
FDK22KXE6D
FDK28KXE6D
FDK36KXE6D
FDK45KXE6D
FDK56KXE6D
FDK71KXE6D
FDUH22KXE6D
FDUH28KXE6D
FDUH36KXE6D
FDE36KXE6D
FDE45KXE6D
FDE56KXE6D
FDE71KXE6D
FDE112KXE6D
FDE140KXE6D
60Hz only
INVERTER DRIVEN MULTI-INDOOR-UNIT
CLIMATE CONTROL SYSTEM
Air-Conditioning & Refrigeration Systems Headquarters
16-5, 2-chome, Kounan, Minato-ku, Tokyo, 108-8215, Japan
Fax : [phone]
No.108 R

'10 • KX-SM-148
CONTENTS
1 OUTLINE OF OPERATION CONTROL BY MICROCOMPUTER ..................... 1
1.1 Wired remote controller (Opition parts) ......................................................... 1
1.2 Operation control function by the indoor controller ....................................... 2
1.3 Operation control function by the remote controller ...................................... 8
1.4 Operation control function by the outdoor controller ..................................... 9
2 SYSTEM TROUBLESHOOTING PROCEDURE ............................................. 40
2.1 Basics of troubleshooting ............................................................................ 40
2.2 Explanation of troubleshooting.................................................................... 41
2.3 Contents of troubleshooting ........................................................................ 42
2.4 Outdoor unit control PCB replacement procedure ...................................... 97
2.5 Inverter PCB replacement procedure.......................................................... 99
3 ELECTRICAL WIRING ................................................................................. 103
3.1 Outdoor unit .............................................................................................. 103
3.2 Indoor unit ................................................................................................. 105
4 PIPING SYSTEM............................................................................................ 123
5 APPLICATION DATA .................................................................................... 125
5.1 Installation of outdoor unit ......................................................................... 125
(1) Ceiling cassette-4 way type (FDT)..................................................... 126
(2) Ceiling cassette-4 way compact type (FDTC).................................... 131
(3) Ceiling cassette-2 way type (FDTW) ................................................. 136
(4) Ceiling cassette-1 way compact type (FDTQ) ................................... 139
(5) Ceiling cassette-1 way type (FDTS) .................................................. 147
(6) Duct connected-High static pressure type (FDU) .............................. 150
(7) Duct connected-Low/Middle static pressure type (FDUM)................. 153
(8) Duct connected (thin)-Low static pressure type (FDUT).................... 156
(9) Duct connected-Compact and Flexible type (FDUH)......................... 159
(10) Wall mounted type (FDK) .................................................................. 162
(11) Ceiling suspended type (FDE)........................................................... 165
(12) Floor standing-2 way type (FDFW) .................................................... 168
(13) Outdoor air processing unit (FDU-F).................................................. 171
5.2 Electric wiring work instruction .................................................................. 174
5.3 Installation manual for wired remote controller (Option parts : RC-E4)..... 179
5.4 Installation of outdoor unit ......................................................................... 184
5.5 Method for connecting the accessory pipe................................................ 200
5.6 Check operation procedure....................................................................... 201
5.7 Instructions for installing the branch pipe set ............................................ 209
6 CORROSION PROTECTION TRETMENT SERIES ...................................... 213

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'10 • KX-SM-148
1. OUTLINE OF OPERATION CONTROL BY MICROCOMPUTER
1.1 Wired remote controller (Option parts)
The gure below shows the remote controller with the cover opened. Note that all the items that may be displayed in the liquid crystal
display area are shown in the gure for the sake of explanation.
Characters displayed with dots in the liquid crystal display area are abbreviated.
Pull the cover downward to open it.
＊ All displays are described in the liguid crystal display for explanation.
The figure below shows the remote control with the cover opened.
Installation of remote control
DO NOT install it on the following places in order to avoid malfunction.
(1) Places exposed to direct sunlight
(2) Places near heat devices
(3) High humidity places
(4) Hot surface or cold surface enough to generate condensation
(5) Places exposed to oil mist or steam directly
(6) Uneven surface
Cover
This button is used to fix the setting.
This button is used to set the silent mode.

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1.2 Operation control function by the indoor controller
(1) Operations of functional items during cooling/heating
Cooling Heating
Dehumidify
Fan
Operation
Functional item
Thermostat
ON
Thermostat
ON
Thermostat
OFF
Thermostat
OFF
Hot start
(Defrost)
Compressor
4-way valve
Outdoor fan
Indoor fan
Louver motor
Drain pump (4)











/
(2)




(2)



 / 
/



 / 
/
/(2)

()
()
 / 
/
/

/
/
/
Thermostat ON: 
Thermostat OFF: (2)
Note (1) : Operation : Stop /: Turned ON/OFF by the control other than the room temperature control.
(2) ON during the drain motor delay control
(3) Drain pump ON setting may be selected by the indoor unit function setting of the wired remote controller.
(2) Dehumidifying operation
(a) When the humidity sensor is not provided (Models other than FDT Series)
return air thermistor [ThI-A (by the remote controller when the remote control sensor is enabled)] controls the indoor
temperature environment simultaneously.
1) Operation is started in the cooling mode. When the difference between the return air thermistor and the setting
temperature is 2°C or less, the indoor unit fan tap is brought down by one tap. That tap is retained for 3 minutes
after changing the indoor fan tap.
Note (1) In case of “P-Hi”, change the tap down to “Hi”.
(2) Lower limit of tap-down for the indoor air volume is Lo tap.
2) If the suction air temperature exceeds the setting temperature 3°C or more during defrosting operation, the indoor
fan tap is raised by one tap. That tap is retained for 3 minutes after changing the indoor fan tap.
Note (1) Upper limit of tap-up for the indoor air volume is the setting air volume.
3) If the thermostat OFF is established during the above control, the indoor fan tap at the thermostat ON is retained so
far as the thermostat is turned OFF.
4) After stopping the cooling operation, the indoor unit continues to run at Lo for 15 seconds.
(3) Timer operation
(a) Timer
Set the duration of time from the present to the time to turn off the air-conditioner.
It can be selected from 10 steps in the range from “OFF 1 hour later” to “OFF 10 hours later”. After the clock timer
setting, the remaining time is displayed with progress of time in the unit of hour.
(b) OFF timer
Time to turn OFF the air-conditioner can be set in the unit of 10 minutes.
(c) ON timer
Time to turn ON the air-conditioner can be set. Indoor temperature can be set simultaneously.
(d) Weekly timer
Timer operation (ON timer, OFF timer) can be set up to 4 times a day for each weekday.
(e) Timer operations which can be set in combination
Timer
OFF timer
ON timer
Weekly timer
Timer



OFF timer



ON timer



Weekly timer



Note (1) : Allowed : Not
W
ESP-FP-1730

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'10 • KX-SM-148
(4) Remote controller display during the operation stop
(a) “Centralized control ON” is displayed always on the LCD under the “Center/Remote” and “Center” modes during the
operation stop (Power ON). This is not displayed under the “Remote” mode.
(b) If this display is not shown under the “Center/Remote” mode, check if the indoor unit power switch is turned on or not.
(5) Hot start (Prevention of cold draft during heating)
At the startup of heating operation, at resetting the thermostat, during defrosting operation and at returning to heating, the
indoor fan is controlled by the indoor heat exchanger temperature (detected with ThI-R) to prevent the cold draft.
Judgment by heating start thermostat
Normal condition/Set airflow volume
Thermostat OFF Thermostat ON
Compressor OFFCompressor ON End of defrosting
Heat exchanger temp. 35˚C or higher, or after 7 minutes Heat exchanger temp. 35˚C or higher, or after 7 minutes
Defrosting start
Fan
Lo
or ULQ
Lo
or ULo
Set airflow volume
Set airflow volume
Indoor heat exchanger temp. (˚C)
Indoor heat exchanger temp. (˚C)
35
35 45
25 35
Indoor heat exchanger temp. (˚C)
Set airflow volume
Fan
OFF
Lo
or ULo
25 35 45
Set airflow volume
Fan
OFF
Indoor heat exchanger temp. (˚C)
Fan
Lo
or ULo
（1）
Note (1) Heating preparation is displayed during the hot start (when the compressor is operating and the indoor fan does not provide the set airow volume).
(6) Hot keep
Hot keep control is performed at the start of the defrost control.
(a) Control
1) When the indoor heat exchanger temperature (detected with ThI-R1 or R2) drops to 35°C or lower, indoor fan is
changed to the lower tap at each setting.
2) During the hot keep operation, the louver horizontal control signal is transmitted.
(b) Ending condition
When the indoor fan is at the lower tap at each setting, it returns to the set airow volume as the indoor heat exchanger
temperature rises to 45°C or higher.
(7) Fan control during the heating thermostat OFF
When the heating thermostat is turned OFF, the setting of the fan control is selectable with using the indoor function of wired
remote controller [ ].
(a) Low speed (Factory default)
If the indoor heat exchanger temperature drops 35°C or lower with the heating thermostat OFF, the indoor fan operate at
the lower speed tap at each setting.
(b) Set airow volume
Even if the indoor heat exchanger temperature drops 35°C or lower with the heating thermostat OFF, the indoor fan
continues to run at the set airow volume.
(c) Intermittent operation
If the indoor heat exchanger temperature drops 35°C or lower with the heating thermostat OFF, the indoor fan operates at
the lower speed tap at each setting and, when the indoor heater exchanger temperature drops 25°C or lower, the indoor fan
stops for 5 minutes. Then the fan runs at the slow speed tap for 2 minutes, and the judgment is made by the thermostat.
(d) Stop
If the indoor heat exchanger temperature drops 35°C or lower with the heating thermostat OFF, the indoor fan is turned
OFF. The same applies also when the remote controller sensor is effective.

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(8) Filter sign
As the operation time (when ON/OFF switch is at ON) accumulates to 180 hours (1), “Filter cleaning” is displayed on the
remote controller. (This is also displayed when the unit is in trouble and under the centralized control, regardless of ON/OFF)
Note (1) Time setting for the lter sign can be made as shown below using the indoor function of wired remote controller “Filter sign setting”. (It is set at 1 at the
shipping from factory.)
Filter Sign Setting
Setting 1
Setting 2
Setting 3
Setting 4
Function
Setting time: 180 hrs (Factory default)
Setting time: 600 hrs
Setting time: 1,000 hrs
Setting time: 1,000 hrs (Unit stop)
(2)
(2) After the setting time has elapsed, the “Filter cleaning” is displayed and, after operating for 24 hours further (counted also during the stop), the unit stops.
(9) Auto swing control [Applicable model: FDT, FDTC, FDTW FDTS, FDTQ (Excepted duct panel) and FDE]
(a) Louver control
(i) Press the [Louver] button to operate the swing louver when the air conditioner is operating.
“Auto wind direction” is displayed for 3 seconds and then the swing louver moves up and down continuously.
(ii) To x the swing louver at a position, press one time the [Louver] button while the swing louver is moving so that
four stop positions are displayed one after another per second.
When a desired stop position is displayed, press the [Louver] button again. The display stops, changes to show the
“Louver stop” for 5 seconds and then the swing louver stops.
(iii) Louver operation at the power on
The louver swings one time automatically (without operating the remote controller) at the power on.
This allows inputting the louver motor (LM) position, which is necessary for the microcomputer to recognize the
louver position.
Note (1) If you press the Louver button, the swing motion is displayed on the louver position LCD for 10 second. The display changes to the “Auto wind
direction” display 3 seconds later.
(b) Automatic louver level setting during heating
While hot start operation and heating thermostat OFF operation, the louver keeps the level position (In order to prevent
the cold draft) whether the auto swing switch is operated or not (auto swing or louver stop), The louver position display
LCD continues to show the display which has been shown before entering this control.
(c) Louver-free stop control
When the louver-free stop has been selected with the indoor function of wired remote controller “Louver control setting”,
the louver motor stops when it receives the stop signal from the remote controller. If the auto swing signal is received
from the remote controller, the auto swing will start from the position where it was before the stop.
Note (1) When the indoor function of wired remote controller “Louver control setting” has been switched, switch also the remote control function “Louver
control setting” in the same way.
(d) Individual flap (louver) control system
Regarding FDT and FDTC models, the individual f laps (louvers) for 4 directions can be controlled to swing within the
ranges between upper limit and lower limit selected with wired remote control respectively.
For detail setting method, refer to ⑦ in page 135 for FDTC or ⑨ in page 130 for FDT.
The single f lap (louver) of FDE model can also be controlled to swing like FDT and FDTC.(refer to ⑪ in page 000 for details)
Note (1) The function is not able to be set with wireless remote controls or simple remote control (RCH-E3)
(10) Compressor inching prevention control
(a) Once the indoor unit thermostat has been turned ON, the thermostat is not turned OFF for 2 minutes (*1) after the
compressor ON even if the thermostat is turned OFF at the state of (1).
(b) When the oil return control has started while the thermostat is turned ON, the thermostat is not turned OFF even if the
thermostat OFF condition is met during the oil return control.
Thermostat ON/OFF with this control
2 minutes2 minutes
OFF
ON
ON
ON
Stopped by remote controller, etc.
＊1
＊1Even when the thermostat of another indoor
unit is turned ON after the compressor ON,
the thermostat is not turned OFF for 2 minutes
after the compressor ON.
＊1
OFF
OFF
3 minutes delay
Thermostat OFF in the condition of (1)
Compressor
Indoor unit A
Thermostat
Indoor unit B
Thermostat

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(11) Drain motor (DM) control [Applicable type: FDT, FDTC, FDTW, FDTS, FDTQ, FDUM, FDQS and FDU90～140]
(a) Drain motor (DM) start operation at the same time when compressor ON at cooling and dehumidifying mode and
keeps operating for 5 minutes after operation stop, the anomalous stop, thermostat OFF and switching from cooling or
dehumidifying operation to fan or heating operation.
Stop (1)
Indoor unit operation mode
Control A
Control B
Compressor ON
Compressor OFF
Cooling Dehumidifying HeatingFan (2) Note (1) Including the stop from cooling, dehumidifying,
fan and heating operation and the anomalous stop.
(2) Including the “Fan” operation according to the
mismatch of operation modes.
(i) Control A
1) If the oat switch detects any anomalous draining condition, the unit stops with the anomalous stop (displays E9)
and the drain pump starts.
2) The drain motor keeps operating while the oat switch is detecting the anomalous condition.
(ii) Control B
If the oat switch detects any anomalous drain condition, the drain motor is turned ON for 5 minutes, and at 10 seconds
after the drain motor OFF it checks the oat switch. If it is normal, the unit is stopped under the normal condition or, if
there is any anomalous condition, E9 is displayed and the drain motor is turned ON. (The ON condition is maintained
during the drain detection.)
(b) Drain motor (DM) interlock control
(i) Start conditions
Depending on the function setting of the remote controller, the drain motor is turned ON under either one of the
following conditions.
1) During heating operation (Both the thermostat ON/OFF)
2) During heating operation (Both the thermostat ON/OFF) + Fan operation
3) Fan operation
(ii) Stop conditions
The drain motor is turned OFF 5 minutes after the stop of operations 1) to 3) above.
(12) Operation check/drain pump test run operation mode
(a) If the power is turned on when the dip switch (SW7-1) on the indoor PCB is ON state, it enters the mode of operation
check/drain pump test run. It is ineffective (prohibited) to change the switch after turning power on.
(b) When the communication with the remote controller has been established within 60 seconds after turning power on by the
dip switch (SW7-1) ON, it enters the operation check mode. Unless the remote controller communication is established, it
enters the drain pump test run mode.
Note (1) To select the drain pump test run mode, disconnect the remote control connector (CNB) on the indoor PCB to shut down the remote controller
communication.
(c) Operation check mode
There is no communication with the outdoor unit but it allows performing operation in respective modes by operating the
remote controller.
(d) Drain pump test run mode
When the drain pump test run is established, only the drain pump operates, and during operation the protective functions
by the microcomputer of indoor unit become ineffective.
(13) Indoor heat exchanger anti-frost (anti-frost control)
Thermostat OFF control
(a) Thermostat is turned OFF depending on the temperature detected with the heat exchanger sensor (ThI-R1, R2) during
“Cooling” and “Dehumidifying” operations.
1.0
Forced thermostat OFF
Thermostat ON OK
Heat exchanger temperature
5-min timer
Temperature drop
Temperature rising
10°C
(b) For 4 minutes after the thermostat ON, the forced thermostat OFF control for the anti-frost protection is not effective.
a) When temperatures detected by the heat exchanger sensors ThI-R1 and R2 are higher than the anti-frost protection
temperature at 4 minutes after the thermostat ON, the detection starts from the state of thermostat ON.
(c) If the temperature detected with the heat exchanger sensor ThI-R1 or R2 has stayed below the anti-frost protection
temperature (-0.5°C) continuously for 5 minutes after 4 minutes of the thermostat ON operation, then the thermostat is
turned OFF forcibly.
The thermostat will be turned ON if temperatures detected by ThI-Ra and R2 picked up in the thermostat ON range.
(d) “Anti-frost” signal is sent to the outdoor unit.

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(14) Anomalous fan motor (FDT,FDTC,FDFW and FDK only)
Fan motor will be stopped with displaying “E16”, if it has detected the revolutions of 200 rpm or less continuously for 30
seconds at a rate of 4 times within 60 minutes, after starting the motor.
(15) High ceiling control [Applicable type: FDT, FDTC, FDTW, FDTS and FDE]
In the case of indoor unit installed in a higher ceiling room, the airow volume mode control can be changed with the wired
remote controller indoor unit function “FAN SPEED SET”.
--- -- --
PHi - HiPHi - MePHi - Hi - Me
STANDARD
HIGH SPEED1, 2
FAN SPEED SET Hi - Lo Hi - MeHi - Me - Lo
PHi - PHi - Hi - Me
PHi - Hi - Me - Lo
Indoor unit airflow setting
Fan tap
Note (1) Factory default is Standard.
(2) At the hot-start and heating thermostat OFF, or other, the indoor unit fan is operated at the low speed tap of each setting.
(3) This function is not able to be set with wireless remote comtrols or simple remote control (RCH-E3)
(16) Hot start
Indoor fan motor control is performed at the start of heating operation.
(a) When the temperature detected with the indoor heat exchanger thermistor (ThI-R1 or ThI-R2) drops 35°C or lower, it
control the fan with AC motor: Lo and DC motor: ULo.
(b) When the heat exchanger thermistor detects 45°C or higher with the fan running at Lo/ULo, it returns to the set airow
volume.
Set airflow volume
Lo/ULo
35°C 45°C
Heat exchanger thermistor temp. (ThI-R1 or R2)
(c) On the indoor unit of which the thermostat has been turned OFF during heating operation, the fan is turned OFF if the
heat exchanger thermistor temperature (Thi-R1 or Thi-R2) drops 25°C or lower.
(17) Detection room temperature compensation during heating
With the standard specication, the compressor is turned ON/OFF based on the setting temperature of thermostat. However,
when the thermostat OFF is likely to occur earlier because the unit is installed in a condition that warm air tends to accumulate
near the ceiling, the setting can be changed by using the indoor function of wired remote controller “Heating room temperature
compensation”. Since the compressor is turned ON/OF at one of the setting temperature at +3, +2 or +1°C, the feeling of
heating can be improved. However, the upper limit of setting temperature is 30°C.
Operation
Setting temperature
Room temp. (deg)
–1 +1
Stop
Standard
Compressor
Operation
Setting temperature
Room temp. (deg)
+4+2
Stop
With setting at +3°C
Compressor
(18) Return air temperature compensation
This is the function to compensate a difference between the detected temperature of the Return air thermistor and the measured
temperature after installation of unit.
(a) It is adjustable in the unit of 0.5°C by using the indoor function of wired remote controller “Return air thermistor
compensation”.
• +1.0°C, +1.5°C and +2.0°C • −1.0°C, −1.5°C and −2.0°C
(b) Since the compensated temperature is transmitted to the remote controller and the outdoor unit, it is controlled with the
compensated temperature.
Note (1) Compensation of detection temperature is effective for the indoor unit sensor only.
(19) External control (Remote display)/Remote operation
Always connect the wired remote controller. Otherwise, you cannot perform the remote operation.
(a) Output for external control (remote display) (Optional remote RUN/STOP monitor kit can be utilized.)
Following output connectors (CNT) are provided on the indoor control PCB. Connect the remote RUN/STOP monitor kit
and pick up respective dry contact signal.
• Operation output: Outputs DC12V relay drive signal during operation.

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• Heating output: Outputs DC12V relay drive signal during heating operation.
• Compressor ON output: Outputs DC12V relay drive signal when the compressor is operating.
• Error output: When any anomalous condition occurs, it outputs DC12V relay drive signal.
(b) Remote operation input
Remote operation inputs (switch input, timer input) connectors (CnT) are provided on the indoor control PCB.
However, the remote operation by the CnT is not effective when “Center mode” is selected with the air-conditioner.
(i)
At the shipping from factory [Indoor function of wired remote controller “External input selector” is
set at the level input.]
• Startup at the input signal to CnT OFF  ON [Edge input] … Air-conditioner ON
• Stop at the input signal to CnT ON  OFF [Edge input] … Air-conditioner OFF
*ON
ONON
OFF OFF
OFF OFF
OFF OFF
ONON
ONON
OFF
OFF
*ON
CnT input
Air-conditioner A
Air-conditioner B
(ii) When the setting is changed to the pulse input at site using the indoor unit function of wired
remote controller “External input selector”
It becomes effective only when the input signal to CnT is changed OFF➝ON and the air-conditioner operation [ON/
OFF] is inverted.
ON
ON
OFF
OFF OFF
OFF
ON
OFF
OFF
ON
ON
CnT input
Air-conditioner A
Air-conditioner B
(c) Processing of emergency stop signal
This emergency stop signal is used to stop all indoor unis connected to the same outdoor unit in emergency.
(i) The emergency stop control becomes effective if the emergency stop control setting is changed to “Valid” from the
wired controller.
(ii) If the emergency stop [E-63] signal is received from outdoor unit, it is transmitted to the remote controller and
makes stop.
(d) Fresh air processing operation input
(i) If indoor unit controller receive fresh air processing operation signal (*1) or fresh air processing stop signal from
remote controller, it output ON signal or OFF signal from CnD connector respectively.
*1. Operation switch ON at interlock setting and ventilation switch ON at non-interlock setting.
(ii) Output relay is DC12V option and maximum relay load is LY2F (OMRON).
(iii)
In case of interlock setting, if either of indoor units connected to one remote controller is in the state of anomalous stop,
the fresh air processing unit connected to that indoor unit cannot be operated. Other processing units connected to the
indoor units operating normally can be operate.
In case of non-interlock setting, processing unit can start ventilation even though the connected indoor unit is in
anomalous stop.
(iv) In case of interlock setting if indoor unit stops, processing unit also stop.
(v) In case of interlock setting if indoor unit stops with anomalous stop, processing unit also stop.
(vi) If indoor unit is started or stopped from center console, processing unit can start or stop in case of interlock setting,
but it keep stopping in case of non-interlock setting.
(vii) Interlock or non-interlock can be set only on the remote controller.
(20) Dip switch function
Model capacity selection with SW6 0 : OFF, 1 : ON
Model P22 P28 P36 P45 P56 P71 P80 P90 P112 P140 P160 P224 P280
SW6-1 0 1 0 0 0 0 1 0 1 0 1 0 1
SW6-2 0 0 1 0 1 0 0 1 1 0 0 1 1
SW6-3 0 0 0 1 1 0 0 0 0 1 1 1 1
SW6-4 0 0 0 0 0 1 1 1 1 1 1 1 1
Note (1) ON marked with * means ON by a remote
controller switch or other.

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1.3 Operation control function by the remote controller
(1) Switching sequence of the operation mode switches of remote controller
Dehumidifying Cooling Fan Heating
(2) [CPU reset]
When the “CHECK” and “GRILL” buttons on the remote controller are pressed at the same time, this function is activated.
This function is same as power supply reset.
(3) [Power failure compensation function]
• This function becomes effective when “POWER FAILURE COMPENSATION SET” is valid by setting the remote controller
functions.
• The remote controller's status is always stored in memory, and after recovery of power, operation is resumed according to
the memory contents. However the auto swing stop position and timer mode are cancelled, but the weekly timer setting is
restored with the holiday setting through all weekdays.
By resetting the clock and cancelling the holiday setting for each weekday after recovery of power, weekly timer setting
becomes effective.
• Contents stored in memory for power failure compenstion are as follows.
Note (1) Item ➅➆ and ➇ are stored in memory regardless of whether the power failure compensation setting is valid or invalid, and silent mode setting is
cancelled regardless of whether the power failure compensation setting is valid or invalid.
➀ Running or Stopping status just before power failure
If it had been operating under OFF timer mode or simple timer mode, memorzed status is as stopping (At the
recovery of power, the timer mode is cancelled but weekly timer setting is changed to the holiday setting through all
weekdays
➁ Operation mode
➂ Fan speed mode
➃ Room temperature setting
➄ Louver auto swing/stop
However, the stop position (position 4) is cancelled and is becomes the level position (position 1).
➅ “Remote control function items”, set with the remote controller function setting (“Indoor unit function items” are
stored in the inoor unit's memory.)
➆ Upper limit value and lower limit value set by temperature setting control.
➇ Clock timer setting and weekly timer setting (Other timer settings are not sotred in memory).
[Parts layout on remote controller PCB]
XY
SW2
SW1
A
B
M
S
親
子
SW1
SW2
When using multiple remote controllers, the following dispiays or settings
cannot be done with the slave remote controller. It is available only with
the master remote controller.
Louver position setting (set upper or lower limit of swinging range)
Setting indoor unit functions
Setting temperature range
Operation data display
Error data display
Silent mode setting
Test operation of drain pump
Change the address set by autamatic address setting method (Kx multi only)
Address setting of master indoor unit (Kx multi only)
Remote controller sensor setting
Remote controller sensor setting
Master/ slave setting when more than one remote controllers are used
A maximum of two remote controllers can be connected to one indoor unit (or one group of indoor units.)
Remote controller cord (no polarity)
Remote controller
SW1 "Master"
Switch Setting Contents
M Master remote controller
SW1 S Slave remote controller
Remote controller
SW1 "Slave"
Indoor units
Note (1) Don’t change SW2 because it is not used normally.
Caution
➈
➉

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1.4 Operation control function by the outdoor controller
(A) Normal control
(1) Operation of major functional components under each operation mode
Operation mode
Fonctional item
Cooling/Dehumidifying
Fan
Heating
Thermostat
ON
Thermostat
OFF Defrost
Thermostat
ON
Thermostat
OFF
Compressor (CM) 〇××〇×〇
Magnetic contactor CM1 (52X1, 52X2) 〇 〇 ×/〇 〇 〇 〇
Outdoor unit fan mortor (FMo-1) 〇 ×/〇 ×/〇 〇/× ×/〇 〇→×
Outdoor unit fan mortor (FMo-2) 〇/× ×/〇 ×/〇 〇/× ×/〇 〇→×
4 way valve (20S) × × × 〇 〇 〇→×
Heating electronic expansion valve
(EEVH) Fully open Fully open ※1
Opening Angle
Control
※2
Fully closed /
Fully open
Super cooling coil electronic expansion
valve (EEVSC)
Opening Angle
Control
Fully closed Fully closed Fully closed Fully closed Fully closed
Solenoid valve (SV1) (oil return) 〇/× × × 〇/× × 〇/×
Solenoid valve (SV6) (liquid injection
return) 〇/× 〇/× × 〇/× 〇/× 〇/×
Solenoid valve (SV11) (gas bypass) × × × 〇/× × ×
Crankcase heater (CH) 〇/× 〇/× 〇 〇/× 〇/× 〇/×
Note (1) It means 〇: ON, ×: OFF, 〇/× : -, ×/〇 : ON or OFF.
(2) This shows the state of output when all indoor units are under the same mode.
(3) ※1 : When stopped from cooling, it is fully open
When stopped from heating, it is fully closed unless another degree of opening is specified by the electronic expansion valve (EEV) control at the
stop.
※2 : When stopped from heating, it is fully closed unless another degree of opening is specified by the electronic expansion valve (EEV) control at the
stop.
M
ESP-FP-1736

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(2) Compressor pre-start control
(a) Remote controller full stop →Operation
(i) Start conditions
• When it has changed to the compressor operation frequency command > 0 Hz. from the state of compressor
stopping.
(ii) Control contents
• It sets the compressor operation frequency command = 0 Hz, and then after this control ends. It starts the
compressor.
(iii) End conditions
When all of the following conditions are satised
①It has elapsed 15 seconds after the start of this control.
• Meaning of marks
52X1, 52X2 Solenoid for compressor CM Compressor
EEVH Heating electronic expansion valve EEVSC Subcooling coil electronic expansion valve
SV6 Solenoid valve [Liquid injection return] ― ―――
ON
15 seconds
6 seconds
Normal control
Normal control
Initial opening
Initial opening
3 minutes
Time
2 minutes
Stop
OFF
Orps
Opening at stop
O pulse
OFF
Start condition established
Operation
52X1, 52X2
CM
EEVH
EEVSC
SV6
ON

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(b) Cooling →Heating
(i) Start conditions
• When the outdoor unit operation mode is changed from the cooling operation to heating operation
(ii) Control contents
1) When the compressor is operating, it makes the compressor stopped.
2) Each functional component operates according to the sequence shown below.
(iii) End conditions
• Meaning of marks
CM
Heating
15 seconds3 minutes
Initial speed
Normal controlInitial opening
Cooling
Any state
Any state
Any state
FMo1, FMo2
20S
EEVH
EEVSC
OFF
Fully open
Fully closed
Fully closed
Time
Start conditions established
OFF
ON
CM Compressor EEVH Heating electronic expansion valve
FMo1, FMo2 Fan motor EEVSC Subcooling coil electronic expansion valve
20S 4-way solenoid valve ― ―――

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(c) Heating →Cooling
(i) Start conditions
• When the outdoor unit operation mode is changed from the heating operation to cooling operation
(ii) Control contents
1) When the compressor is operating, it make the compressor stopped.
2) Each functional component operates according to the sequence shown below.
(iii) End conditions
Note (1) ※: It is fully closed till the end of 3-minute delay after the automatic reset.
• Meaning of marks
CM
FMo1, FMo2
20S
EEVH
EEVSC
ON
Heating
Cooling
15 seconds3 minutes
Initial opening
Fully closed（※）
Time
Start conditions established
Normal control
Initial speed
Any state
Any state
Any state
Fully closed
OFF
OFF
Fully open
CM Compressor EEVH Heating electronic expansion valve
FMo1, FMo2 Fan motor EEVSC Subcooling coil electronic expansion valve
20S 4-way solenoid valve ― ―――

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(3) Compressor control
(a) 4-way valve switching safeguard
In order to switch 4-way valve completely, it makes the compressor speed increasing as follows.
(i) This control starts to increases the compressor speed from 10 Hz after the compressor pre-start control ends.
(ii) The target compressor speed is shown in following table.
(b) Compressor protection start
After the 4-way valve switching safeguard, the compressor is controlled with the following compressor protection start.
➀ Compressor protection start, normal
➁ Compressor protection start A
➂ Compressor protection start B
(i) Compressor protection start, normal
< Control contents >
Compressor maintains operation at lower limit frequency. after 4-way valve switching safeguard ends.
(During this control, compressor speed is prohibited to increase.)
After this control ends, comperssor speed is governed by the compressor speed control.
< End conditions >
When either one of the following conditions is established
a) When it has elapsed 1 minute and 45 seconds after the start
(ii) Compressor protection start A
< Control contents >
➀ Compressor maintatins operation at lower limit frequency, after 4-way valve switching safeguard ends.
If the time from starting till reaching the lower limit frequency after 4-way valve switching safeguard operation
has elapsed lminute, the target frequency is chnged to that of lminuted later from the lower limit frequency.
➁ During this control, the target frequency is increased at a rate of 5 Hz/minute from the lower limit frequency.
(Note) The starting point of this control is the completion point of inverter start (10 Hz).
Item
Model
4-way valve switching assurance/Target compressor speed
Frequency (Fk) Speed (rps)
FDC(S)224KXE6M 70 50
FDC(S)280KXE6M
FDC(S)335KXE6M 71 42
Initial start remote
controller ON
error reset
Thermostat ON start
Operation mode
is changed during
thermostat OFF
Operation mode is
not changed during
thermostat OFF
Compressor ON
Initial
Less than 45 min
after power ON
Compressor
protection start B
Compressor
protection start B
Compressor
protection start B
45 min. or more
after power ON
Compressor
protection start A
Compressor
protection start A
Compressor
protection start A
Compressor ON
Second & later
Less than 45 min
after stop
Compressor normal
protection start
Compressor normal
protection start
Compressor normal
protection start
45 min. or more
after stop
Compressor
protection start A
Compressor
protection start A
Compressor
protection start A
10 20 3025 40 50 60 70
Lower limit frequency
Speed control
Start
Time (second)
80 90 105 120
60
40
20
10
Compressor inverter frequency (Hz)

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< End conditions >
When either one of following conditions is established
a) When the frequency upper limit increase by this control continued for 15 minutes in total
When the inverter has stopped within 15 minutes after the start and is started again, it starts with the normal
protection start and increases the frequency upper limit at a rate of 5 Hz/minute till the frequency increase
continues for 15 minutes in total.
b) Overheat temperature under the compressor dome
≧
20℃
(iii) Compressor protection start B
< Control contents >
➀ Compressor maintains operation at lower limit frequency, after 4-way valve switching safeguard ends.
If the time from starting till reaching the lower limit frequency after 4-way valve switching safeguard operation
has elapsed 2 minutes, the target frequency is changed to that of 2 minutes later from the lower limit frequency.
➁ For 18 minutes after the starting, the target frequency is increased at a rate of 5 Hz/2 minutes from the lower limit
frequency.
➂ For 18 minutes after starting, the starting point of this control is the completion point of inverter start (10 Hz).
➃ From 18 minutes to 24 minutes, it is increased at a rate of 5 Hz/minute.
< End conditions >
When either one of the following conditions is established
(a) This frequency-up control will end when the cumulative operation time after starting becomes 24 minutes.
If the inverter stopped within 24 minutes after starting and starts again, it starts with "Compressor protection
start, normal" and increases the frequency at a rate of 5 Hz/minute till the cumulative operation time after
starting becomes 24 munutes.
However, if 45 minutes have been elapsed since inverter stopped and starts again, it starts with "Compressor
protection start A".
(b) Overheat temperature under the compressor dome ≧ 20℃
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
120
100
80
60
40
20
Compressor inverter frequency (Hz)
Upper limit frequency
Speed control
Lower limit frequency
Time (minute)
Start
0 2 4 6 8 10 12 14 16 18 20 22 24
120
100
80
60
40
20
Compressor inverter frequency (Hz)
Time (minute)
Start
Speed control
Upper limit frequency
Lower limit frequency

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(4) Outdoor fan control
(a) Outdoor fan speed and fan motor rotation speed.
The 7th outdoor fan speed in the following table is specied as the rated speed. Under the normal control, the speeds up
to 8th level (800 min-1) are used.
Note (1) Figures in the parentheses in the above table are applicable to FDC(S)224KXE6M.
(b) Fan control during cooling
During cooling and dehumidifying, fan speed is controlled in accordance with the high pressure (sensed by PSH) and the
outdoor air temperature (sensed by Tho-A).
(i) Initial fan speeds are as follows.
Initial ourdoor fan speed at cooling
(ii) During normal operation, the speed is changed in accordance with the high pressure value.
➀ When it has detected HP ≧ 2.2 MPa for 1 minute continuously, the fan speed is raised by one tap.
➁ When it is 1.5 MPa < HP < 2.2 MPa, the present fan speed is maintained.
➂ When it has detected HP ≦ 1.5 MPa for 1 minute continuously, the fan speed is dropped by one tap.
➃ Control range of fan speed is 1th – 8th speeds.
(iii) When states under this control change from HP < 3.3 MPa to HP ≧ 3.3 MPa, the fan speed is changed preferentially
to the followings. (After the change it returns to the normal control.)
➀ When the outdoor air temperature ≧ 30ºC, it changes to 7th or higher speed.
➁ When the outdoor air temperature < 30ºC, it changes to 3th or higher speed.
➂ When the fan speed was higher than the above before the change of states, the fan speed is not changed.
Outdoor fan tap Cooling Heating
FMo1 [min-1] FMo2 [min-1] FMo1 [min-1] FMo2 [min-1]
0th speed 0 0 0 0
1th speed 200 0 200 0
2th speed 200 200 200 200
3th speed 300 300 300 300
4th speed 400 400 400 400
5th speed 500 500 500 500
6th speed 575 575 575 575
7th speed 700 700 700 700
8th speed 800 800 800 (780) 800 (780)
Model Outdoor air temp ≤ 10ºC 10ºC < Outdoor air Temp. < 15ºC 15ºC ≤ Outdoor air Temp.
All models 2th speed 4th speed 6th speed
1.5 2.2
One tap up
Maintained
One tap down
High pressure (MPa)

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(c) Outdoor fan cooling control at low outdoor air temperature.
(i) Start conditions
This control is performed when all of following conditions is established.
➀ When the ordinary outdoor fan control is performed
➁ Outdoor air temperature ≦ 10ºC (It is reset with the hysteresis of the outdoor air temperature > 15ºC.)
➂ Outdoor fan speed = 1st speed (200 rpm)
(ii) Control contents
➀ Initial fan speed is 200 rpm
➁ If the following high pressure is detected for 20 seconds continuously, fan speed will be changed
➂ Outdoor fan speed is in a range of 130 rpm – 300 rpm.
(iii) End conditions
When either one of following conditions is established
➀ When the ordinary outdoor unit fan cooling control ends
➁ Outdoor air temperature > 15ºC
➂ Outdoor unit fan speed ≧ 2th speed
(Note) This control range is not more than 300 rpm × 1 fan.
(d) Outdoor fan heating control
The fan speed control is performed based on the low pressure (detected with PSL) during heating operation.
(i) Initial fan speed is 6th speed.
(ii) Speed is changed depending on the low pressure value.
➀ When it is detected LP ≦ 0.75 MPa for 30 seconds continuously, the fan speed is raised by 1 tap.
➁ When it is 0.75 MPa < LP < 0.85 MPa, the present fan speed is maintained.
➂ When it is detected LP ≧ 0.85 MPa for 30 seconds continuously, the fan speed is dropped by 1 tap.
➃ Control range of fan speed is 1st – 8th speeds.
(iii)

When states change from LP < 1.0 MPa to HP ≧ 1.0 MPa during this control, the fan speed is changed
preferentially to the following. (It returns to the normal control after the change.)
➀ It changes to 4th or lower speed.
➁ If the fan speed was lower than the above speed before the change of states, the fan speed does not change.
Valid
Invalid
10 15
Outdoor air temperature
1.4 1.7
+10 rpm
−10 rpm
Maintained
High pressure (MPa)
0.75
Low pressure (MPa)
0.85
One tap up
One tap down
Maintained

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(5) Defrost control
(a) Temperature condition of defrosting
1)  Start conditions (Standard specication or cold region specication can be selected by switching the jumper
wire J15.)
Defrost operation will start, when outdoor unit whose compressor is operating under heating mode has satised all
the following conditions.
(i) When 33 minutes of cumulative compressor operation time has passed since heating operation started.
(ii) When 33 minutes of cumulative compressor operation time has passed since the previous defrosting ended.
(iii) When 8 minutes has passed since the compressor turned ON from OFF status.
(iv) When 8 minutes has passed since one outdoor fan turned ON from OFF status.
(v) After all above conditions have been met, when any of the following conditions is satised.
➀ When the outdoor heat exchanger temperature (sensed by Tho-R) and the outdoor air temperature (sensed
by Tho-A) dropped below the defrosting start temperature in Fig. 1 for 30 seconds continuously
➁ When the suction pressure saturated temperature calculated by the low pressure (sensed by PSL) and the
outdoor air temperature (sensed by Tho-A) dropped below the defrosting start temperature in Fig. 2 for 3
minutes continuously
TR: Heat exchanger temperature. (°C)
TA: Outdoor air temperature. (°C)
TA: Outdoor air temperature. (°C)
Fig. 1
Cold region
Standard
(Factory setting)
Defrost start zone
-2
-6
-15
-19
-21
-25
-20 -15 6
Without J15
Cold region specification
With J15
SST: Suction pressure saturated temperature. (°C)
Fig. 2
Cold region
Standard
(Factory setting)
Defrost start zone
-6
-10
-19
-23
-25
-29
-20 -15 6
Without J15
Cold region specification
With J15
2) End conditions
• Standard (J14 is shorted)
a) When the temperature detected with both outdoor heat exchanger temperature thermistors (Tho-R1 and
Tho-R2) is higher than 9ºC
b) Or when 12 minutes have elapsed since defrosting started.
• Cold region setting (J14 is open)
a) When (Tho-R1 and Tho-R2) >
= 9ºC is satised, after 2 minutes and 30 seconds have elapsed since defrosting
started, and when either of following conditions is satised, the defrosting end operation starts.
i) 2 minutes and 30 seconds have elapsed since the temperature of either Tho-R1 or Tho-R2 was 14ºC or
higher
ii) The temperature of either Tho-R1 or Tho-R2 is 30ºC or higher.
iii) 14 minutes have elapsed since defrosting started.
b) When (Tho-R1and Tho-R2) < 9ºC is satised, after 2 minutes and 30 seconds have elapsed since defrosting
started, and when either of following conditions is satised, the defrosting end operation starts.
i) 5 minutes have elapsed since the temperature of either Tho-R1 or Tho-R2 was 14ºC or higher.
ii) The temperature of either Tho-R1 or Tho-R2 is 30ºC or higher.
iii) 14 minutes have elapsed since defrosting started.

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(b) Time condition of defrosting
1) Start conditions
Defrosting operation start when any of the following conditions is satised.
(i) When 33 minutes of cumulative compressor operation time has passed since heating operation started.
(ii) When 33 minutes of cumulative compressor operation time has passed since the previous defrosting ended.
(iii) When 105 seconds has passed since the compressor turned ON from OFF status un heating mode.
(iv) When the oil return condition has been established
(v) Following cases are excluded.
➀ When the upper limit frequency of the compressor protection start A or B is lower than the defrosting
frequency
➁ During the normal compressor protection start
2) End conditions
Defrosting operation stops when any of the following conditions is satised.
(i) When 12 minutes has passed since defrost started
(ii) When the outdoor heat exchanger temperature (sensed by Tho-R) is detected 10°C or higher continuously for
10 seconds
(iii) When it has detected the high pressure (HP) ≥3.0MPa
(6) Protective control
(a) Discharge pipe temperature (Td) control
Discharge pipe temperature sensor (Tho-D1) monitors the discharge pipe temperature (Td) to avoid the rise of discharge
pipe temperature.
1) Compressor capacity control
(i) Start conditions
When all of following conditions are satisfied
➀ When the compressor is ON state.
➁ When it detects the discharge pipe temperature (sensed by Tho-D1) is higher than 120ºC
(ii) Control contents
Whenever it detects the discharge pipe temperature is higher than 120ºC for 5 seconds, the capacity is decreased.
(iii) End conditions
When any one of following conditions is satisfied
➀ When the discharge pipe temperature (sensed by Tho-D1) drops below 110ºC
➁ When the compressor is OFF state.
➂ During the defrosting control
2) Indoor EEV slightly open control at heating stop.
Rise of discharge pipe temperature (Td) is restarined by opening the indoor EEV during heating stop.
(b) Over-current protection control (Current safe)
1) If the input current value at the inverter inlet (converter inlet L3-phase) exceeds the setting value, the compressor
speed is reduced. If the higher value persists even after the speed reduction, the speed is reduced further.
2) This control terminates when it is lower than the reset value for 3 minutes continuously or lower than the setting
value for 6 minutes continuously.
(c) Power transistor temperature (PT) protective control
If the power transistor temperature exceeds 75°C, the compressor speed is controlled.
Speed is reduced once each minute
Retention
Release
72 75
Power transistor temp. (°C)