Fujitsu ARU9RLF Original operating manual

SPLIT TYPE
ROOM AIR CONDITIONER
SLIM DUCT type
Models Indoor unit Outdoor unit
INVERTER
SERVICE
INSTRUCTION
R410A
ARU9RLF
ARU12RLF
ARU18RLF
AOU9RLFC
AOU12RLFC
AOU18RLFC

CONTENTS
1. DESCRIPTION OF EACH CONTROL OPERATION
1. COOLING OPERATION................................................................................................
3. DRY OPERATION.........................................................................................................
2. HEATING OPERATION.................................................................................................
5. INDOOR FAN CONTROL..............................................................................................
4. AUTO CHANGEOVER OPERATION............................................................................
7. COMPRESSOR CONTROL..........................................................................................
6. OUTDOOR FAN CONTROL..........................................................................................
9. ELECTRONIC EXPANSION VALVE CONTROL........................................................
8. TIMER OPERATION CONTROL...................................................................................
11. PREVENT TO RESTART FOR 3 MINUTES ( 3 MINUTES ST ).................................
10. TEST OPERATION CONTROL...................................................................................
13. AUTO RESTART.........................................................................................................
12. FOUR-WAY VALVE EXTENSION SELECT................................................................
15. COMPRESSOR PREHEATING..................................................................................
14. MANUAL AUTO OPERATION ( When using the Wireless RC ).................................
16. MIN.(MINIMUM) HEAT OPERATION..........................................................................
17. ECONOMY OPERATION............................................................................................
19. EXTERNAL ELECTRICAL HEATER CONTROL.........................................................
01-01
01-02
01-02
01-03
01-04
01-06
01-07
01-08
01-12
01-12
01-12
01-13
01-13
01-13
01-13
01-14
01-14
18. FRESH AIR CONTROL............................................................................................... 01-14
01-15
01-16
20. DRAIN PUMP OPERATION........................................................................................
01-18
22. OFF DEFROST OPERATION CONTROL...................................................................
21. DEFROST OPERATION CONTROL...........................................................................
01-19
23. VARIOUS PROTECTIONS..........................................................................................
01-12

3. APPENDING DATA
3-1 FUNCTION SETTING.................................................................................................
3-1-1 INDOOR UNIT....................................................................................................
3-1-2 PROCEDURES TO CHANGE THE FUNCTION SETTING................................
03-01
03-01
03-04
3-2 THERMISTOR RESISTANCE VALUES......................................................................
3-2-1 INDOOR UNIT....................................................................................................
3-2-2 OUTDOOR UNIT................................................................................................
03-07
03-07
03-07
2. TROUBLE SHOOTING
2-1 ERROR DISPLAY.......................................................................................................
2-1-1 WIRED REMOTE CONTROLLER DISPLAY......................................................
2-2 TROUBLE SHOOTING WITH ERROR CODE............................................................
2-3 TROUBLE SHOOTING WITH NO ERROR CODE.....................................................
02-01
02-01
02-03
02-25
2-4 SERVICE PARTS INFORMATION.............................................................................. 02-30

1 . DESCRIPTION OF EACH
CONTROL OPERATION
R410A
SLIM DUCT type
INVERTER

( Fig. 1 : Outdoor temperature zone )
1. COOLING OPERATION
Minimum
frequency
Maximum
frequency
AOU9RLFC
AOU12RLFC
AOU18RLFC
10rps
10rps
12rps
Indoor fan mode
Me Lo Quiet
A zone 74rps 49rps 44rps 35rps
B zone 74rps 49rps 44rps 35rps
C zone 74rps 49rps 44rps 35rps
AOU9RLFC
D zone 49rps 40rps 31rps 22rps
E zone 49rps 40rps 31rps 22rps
F zone 49rps 40rps 31rps 22rps
( Table 1 : Compressor frequency range )
01-01
AOU12RLFC
AOU18RLFC
A zone 74rps 49rps 44rps 35rps
B zone 74rps 49rps 44rps 35rps
C zone 74rps 49rps 44rps 35rps
D zone 49rps 40rps 31rps 22rps
E zone 49rps 40rps 31rps 22rps
F zone 49rps 40rps 31rps 22rps
A zone 104rps 59rps 48rps 30rps
B zone 104rps 59rps 48rps 30rps
C zone 72rps 41rps 30rps
D zone 48rps 41rps 34rps 21rps
E zone 48rps 41rps 34rps 21rps
F zone 48rps 41rps 34rps 21rps
48rps
( Table 2 : Limit of maximum speed based on outdoor temperature )
74rps
74rps
104rps
Outdoor
temp. zone Hi
When the compressor operates for 30 minutes continuously at over the maximum frequency ,
the maximum frequency is changed from Maximum Frequency to Maximum Frequency .
A sensor (room temperature thermistor) built in the indoor unit body will usually perceive
difference or variation between a set temperature and present room temperature, and
controls the operation frequency of the compressor.
* If the room temperature is 4°F(2°C) higher than a set temperature, the compressor operation
frequency will attain to maximum performance.
* When the room temperature is between +4°F(+2°C) to -5°F(-2.5°C) of the setting temperature,
the compressor frequency is controlled within the range shown in Table 1.
However, the maximum frequency is limited in the range shown in Fig. 1 based on the
fan speed mode and the outdoor temperature.
* If the room temperature is 5°F(2.5°C) lower than a set temperature, the compressor will be
stopped.
Outside air Outside air
temperature temperature
97°F
(36°C)
A zone
93°F
(34°C) 90°F
(32°C)
B zone
86°F
(30°C) 70°F
(21°C)
C zone
66°F
(19°C)
D zone
E zone
F zone
50°F
(10°C)
32°F
(0°C)
54°F
(12°C)
36°F
(2°C)
Maximum
frequency
57rps
57rps
68rps

2. HEATING OPERATION
( Table 3 : Compressor frequency range )
01-02
Minimum
frequency
Maximum
frequency
AOU9RLFC 10rps 119rps
AOU12RLFC 10rps 119rps
AOU18RLFC 12rps 140rps
3. DRY OPERATION
The compressor frequency shall change according to the temperature, set temperature,
and room temperature variation which the room temperature sensor of the indoor unit body has
detected as shown in the Table 4.
However, after the compressor is driven, the outdoor unit shall run at operation frequency of
40rps (9RLFC), 40rps (12RLFC), 40rps (18RLFC) for a minute.
( Table 4 : Compressor frequency in Dry mode)
Operating
frequency
35rps
35rps
0rps
AOU
9RLFC
X zone
J zone
Y zone
Operating
frequency
J zone
Y zone
X zone 35rps
35rps
0rps
AOU
12RLFC
Operating
frequency
J zone
Y zone
X zone 30rps
30rps
0rps
AOU
18RLFC
A sensor (room temperature thermistor) built in the indoor unit body will usually perceive
difference or variation between a set temperature and present room temperature, and
controls the operation frequency of the compressor.
* If the room temperature is lower by 6°F(3°C) than a set temperature, the compressor operation
frequency will attain to maximum performance.
* If the room temperature is higher 5°F(2.5°C) than a set temperature, the compressor will be
stopped.
* When the room temperature is between +5°F(+2.5°C) to -6°F(-3°C) of the setting temperature,
the compressor frequency is controlled within the range shown in Table 3.
Ts+1°F
(Ts+0.5°C) Ts-1°F
(Ts-0.5°C)
Ts-3°F
(Ts-1.5°C)
Ts+3°F
(Ts+1.5°C)
( Fig.2 : Compressor Control based on Room Temperature )
Room Room
temperature temperature
X zone
J zone
Y zone

4. AUTO CHANGEOVER OPERATION
01-03
( Fig. 3 : Operation flow chart )
START
Room temp.
Room temp.
>Ts+4°F(2°C) ?
COOLING OPERATION
HEATING OPERATION
YES
YES
NO
NO
NO
NO
YES
YES
TS: Setting temperature
<Ts-4°F(2°C) ?
Thermostat remains
in OFF state for 6 minutes or
longer?
System stops
or operation command other than
auto changeover operation?
NO
NO
Thermostat remains
in OFF state for 6 minutes or
longer?
System stops
or operation command other than
auto changeover operation?
YES
YES
When the air conditioner is set to the AUTO mode by remote control, operation starts in the optimum
mode from among the HEATING, COOLING, DRY and MONITORING modes. During operation, the
optimum mode is automatically switched in accordance with temperature changes. The temperature
can be set between 64°F(18°C) and 88°F(30°C) in 2°F(1°C) steps.

5. INDOOR FAN CONTROL
The airflow can be switched in 5 steps such as Auto, Quiet, Low, Med, High,
while the indoor fan only runs.
When fan mode is set at [Auto], it operates on [Med] fan Speed.
01-04
2. FAN OPERATION
3. COOLING OPERATION
Switch the airflow [Auto], and the indoor fan motor will run according to a room temperature,
as shown in Fig. 4.
On the other hand, if switched in [High] [Quiet], the indoor motor will run at a constant airflow of [Cool]
operation modes Quiet, Low, Med, High, as shown in Table 5.
( Fig. 4 : Airflow change - over ( Cooling : Auto ) )
1. Fan speed
( Table 5 : Indoor fan speed )
Operation mode Air flow mode
Speed (rpm)
Cooling/ Fan
Heating
Dry X zone: 960
J zone: 960
X zone: 1030
J zone: 1030
X zone: 1140
J zone: 1140
ARU9RLF ARU12RLF ARU18RLF
4. DRY OPERATION
Refer to the Table 5.
During the dry mode operation, the fan speed setting can not be changed.
High
High
Med
Med
Low
Low
Quiet
Quiet
S-Low
1260
1160
1060
960
500
1340
1240
1140
1030
500
1380
1300
1220
1140
600
1260
1160
1060
960
500
1340
1240
1140
1030
500
1380
1300
1220
1140
600
When the room
temperature rises
When the room
temperature drops
TR : Room temperature
Ts : Setting temperature
TR-Ts > 4°F
(2°C)
2°F > TR-Ts
(1°C)
4°F > TR-Ts > 2°F
(2°C) (1°C)
=
TR-Ts > 5°F
(2.5°C)
=
3°F > TR-Ts
(1.5°C)
5°F > TR-Ts > 3°F
(2.5°C) (1.5°C)
=
High mode
Med mode
Low mode
S-Low

The maximum value of the indoor fan speed is set as shown in Fig. 6 based on the detected
temperature by the indoor heat-exchanger sensor on heating mode.
( Fig. 6 : Cool air prevention control )
01-05
5. HEATING OPERATION
Switch the airflow [Auto], and the indoor fan motor will run according to a room temperature,
as shown in Fig. 5
On the other hand, if switched in [High] [Quiet], the indoor motor will run at a constant airflow
of [Heat] operation modes Quiet, Low, Med, High, as shown in Table 5.
6. COOL AIR PREVENTION CONTROL (Heating mode)
( Fig. 5 : Airflow change - over ( Heating : Auto ) )
108°F
(42°C)
86°F
(30°C)
93°F
(34°C)
Indoor heat exchanger
temperature drops
Hi
Me+
Lo
Cool air
prevention
102°F
(39°C)
99°F
(37°C)
99°F
(37°C)
90°F
(32°C)
S-Lo
Swich the airflow "Auto" at cooling mode, and the indoor fan motor will run as shown in Fig. 7.
7. MOISTURE RETURN PREVENTION CONTROL (Cooling mode& Dry mode)
( Fig. 7 : Indoor fan control )
Compressor
ON
OFF
Indoor fan
Setting air flow
Indoor fan
(as shown in Table 6)
S-Low
OFF
10 30 60 180 60 180 60 10 30
(sec)
( Table 6 : Indoor fan speed )
X zone J zone
ARU9RLF 960rpm 960rpm 960rpm
ARU12RLF 1030rpm 1030rpm 1030rpm
Dry Cooling
108°F
(42°C)
86°F
(30°C)
96°F
(34°C)
Indoor heat exchanger
temperature drops
Powerful
Hi
Lo
Cool air
prevention
102°F
(39°C)
99°F
(37°C)
99°F
(37°C)
90°F
(32°C)
82°F
(28°C)
S-Lo
TR-Ts > -3°F
(-1.5°C)
=
-5°F > TR-Ts
(-2.5°C)
-3°F > TR-Ts > -5°F
(-1.5°C) (-2.5°C)
=
TR-Ts > -2°F
(-1°C)
=
-4°F > TR-Ts
(-2°C)
-2°F > TR-Ts > -4°F
(-1°C) (-2°C)
=
When the room
temperature rises When the room
temperature drops
TR : Room temperature
Ts : Setting temperature
Low mode
Med mode
High mode
*High
or setting fan mode
*Low
or setting fan mode
Indoor heat exchanger
temperature rises Indoor heat exchanger
temperature drops
S-Low
*Lower speed is selected.
75°F
(24°C)
84°F
(29°C)
ARU18RLF 1140rpm 1140rpm 1140rpm

6. OUTDOOR FAN CONTROL
( Table 8 : Outdoor fan speed )
*The outdoor fan speed mentioned above depends on the compressor frequency.
(When the compressor frequency increases, the outdoor fan speed also changes to the higher
speed. When the compressor frequency decreases, the outdoor fan speed also changes to the
lower speed.)
*After the defrost control is operated on the heating mode, the fan speed keeps at the higher speed
as Table 9 without relating to the compressor frequency.
01-06
( Table 9 : Outdoor fan speed after the defrost )
1. Outdoor Fan Motor
2. Fan Speed
AC Motor DC Motor
AOU9 / 12 / 18RLFC
Table 7 shows the type of the outdoor fan motor. The control method is different
between AC motor and DC motor.
( Table 7 : Type of Motor )
AOU9RLFC 1100rpm
Cooling Heating
AOU9RLFC
AOU12RLFC
AOU18RLFC
Y
Z
Zone
Refer to Fig. 8
(rpm)
F
G
Y
Z
F
G
Y
Z
F
G
Dry
250/ 200
300/ 250
300/ 250
1050/ 870/ 720/ 590/ 530
1050/ 870/ 720/ 530
870/ 530/ 300
1050/ 870/ 720/ 590/ 530
870/530/300
1100/ 870/ 780/ 720/ 590/ 480
530
1100/ 870/ 780/ 720/ 590/ 480
1100/ 1000/ 780/ 720/ 590/ 480
870/530/300
250/ 200
300
250/ 200
AOU18RLFC
AOU12RLFC 1100rpm
1100rpm
( Fig. 8 : Outside air temperature zone selection )
70°F
(21°C)
50°F
(10°C)
Outside air
temperature
Outside air
temperature
Z zone
Y zone
F zone
G zone
54°F
(12°C)
36°F
(2°C)
66°F
(19°C)
32°F
( 0°C)
530
530
300/ 250
250/ 200
300/ 250
250/ 200
300
250/ 200

7. COMPRESSOR CONTROL
01-07
1. OPEARTION FREQUENCY RANGE
The operation frequency of the compressor is different based on the operation mode as
shown in the Table 10.
Cooling / Dry Heating
Minimum Maximum Minimum Maximum
AOU9RLFC
AOU12RLFC
10rps
10rps
74rps 10rps 119rps
10rps 119rps
74rps
AOU18RLFC 104rps 16rps
12rps 140rps
AOU9RLFC
AOU12RLFC
AOU18RLFC
AOU9RLFC
AOU12RLFC
AOU9RLFC
AOU12RLFC
AOU9RLFC
AOU12RLFC
AOU18RLFC
(Table 10 : Compressor frequency range)
2. OPEARTION FREQUENCY CONTROL AT NORMAL START UP
The compressor frequency soon after the start-up is controlled as shown in the Fig. 9
(Fig. 9 : Compressor control at start-up)
Time Time Time Time Time
(Frequency)
Frequency Frequency Frequency Frequency Frequency
Frequency
Frequency
Frequency
Frequency
Frequency
Time Time Time Time Time
(Time)
Frequency
Time 6
Frequency
Time 6
40rps 57rps 72rps 80rps 101rps 110rps
40rps 59rps 72rps 80rps 101rps 110rps
80sec 110sec 140sec 200sec 410sec350sec
3. LIMITATION OF COMPRESSOR FREQUENCY BY OUTDOOR TEMPERATURE
The minimum compressor frequency is limited by outdoor temperature as shown in the Table 11.
Under Over Under Over Under Over
35rps 18rps 15rps10rps
(Table 11 : Limitation of Compressor Frequency)
50°F(10°C) 57°F(14°C) 104°F(40°C)
Under Over Under Over Under Over Under Over
35rps 18rps 10rps 16rps29rps
23 °F( - 5°C)
37°F(3°C) 45°F(7°C) 64°F(18°C)
[ Cooling/ Dry ]
[ Heating ]
AOU18RLFC
AOU18RLFC
Under Over Under Over Under Over
24rps 18rps 16rps12rps
32°F(0°C) 50°F(10°C) 104°F(40°C)
Under Over Under Over
24rps 18rps 16rps
37°F(3°C) 45°F(7°C)
[ Cooling/ Dry ]
[ Heating ]

8. TIMER OPEARTION CONTROL
1. ON TIMER/ OFF TIMER
The Table 12 shows the available timer setting based on the product model.
ON TIMER / OFF TIMER PROGRAM TIMER SLEEP TIMER
ARU9/ 12/ 18RLF
OFF timer : When the clock reaches the set time, the air conditioner will be turned off.
Operation mode
Stop mode
Set time of timer
ON timer : When the clock reaches the set time, the air conditioner will be turned on.
Operation mode
Stop mode
Set time of timer
The program timer allows the OFF timer and ON timer to be used in combination one time.
Operation mode
Operation will start from the timer setting (either OFF timer or ON timer) whichever is closest
to the clock's current timer setting.
The order of operations is indicated by the arrow in the remote control unit's display.
SLEEP timer operation cannot be combined with ON timer operation.
( Table 12 : Timer Setting )
2. PROGRAM TIMER
Stop mode Stop mode Stop mode
Operation mode Operation mode
Set time Set time Set time Set time
01-08
8-1 WIRELESS REMOTE CONTROLLER (OPTION)

3. SLEEP TIMER
If the sleep is set, the room temperature is monitored and the operation is stopped automatically.
If the operation mode or the set temperature is change after the sleep timer is set, the operation is
continued according to the changed setting of the sleep timer from that time ON.
Set temperature rises
( Ts : Set temperature )
Stop of operation
Set temperature lowers
( Ts : Set temperature )
Ts
Stop of operation
In the cooling operation mode
When the sleep timer is set, the setting temperature is increased 2°F(1°C).
It increases the setting temperature another 2°F(1°C) after 1 hour.
After that, the setting temperature is not changed and the operation is stopped at the time
of timer setting.
Ts
+2°F(1°C)
+4°F(2°C)
Set 60min
In the heating operation mode
When the sleep timer is set, the setting temperature is decreased 2°F(1°C).
It decreases the setting temperature another 2°F(1°C) every 30 minutes.
Upon lowering 8°F(4°C), the setting temperature is not changed and the operation stops at
the time of timer setting.
-8°F(-4°C)
-6°F(-3°C)
-4°F(-2°C)
-2°F(-1°C)
Set 30min 30min 30min
01-09

01-10
8-2 WIRED REMOTE CONTROLLER
The Table 13 shows the available timer setting based on the product model.
ON TIMER / OFF TIMER WEEKLY TIMER TEMPERATURE SET BACK TIMER
ARU9/ 12/ 18RLF
( Table 13 : Timer Setting )
1. ON / OFF TIMER
OFF timer : When the clock reaches the set time, the air conditioner will be turned off.
Operation mode
Stop mode
Set time of timer
ON timer : When the clock reaches the set time, the air conditioner will be turned on.
Operation mode
Stop mode
Set time of timer
The weekly timer allows up to two ON and OFF time to set up per day.
Use this timer function to set operating time for each day of the week.
Operation mode
The operating time can be set in 30 min increments only.
The OFF time can be carried over to next day.
The ON timer and the OFF timer functions cannot be set with using the weekly timer.
Both ON and OFF time must be set.
2. WEEKLY TIMER
2-1. WEEKLY TIMER
Stop mode Stop mode Stop mode
Operation mode Operation mode
Set time Set time Set time Set time

01-11
The DAY OFF setting is only available for days for which weekly settings already exist.
The SET BACK timer only changes the set temperature for 7 days, it cannot be used to start or stop
air conditioner operation.
The SET BACK timer can be set to operate up to two times per day but only one temperature setting
can be used.
During COOLING/DRY mode, the air conditioner will operate at a minimum of 64°F(18°C) even if
the SET BACK temperature is set to 63°F(17°C) or lower.
The DAY OFF setting can only be set one time. The DAY OFF setting is cancelled automatically
after the set day has passed.
Normal
Next day setting
If the operating time carries over to the next day (during a next day setting), the effective
DAY OFF range will be set as shown below.
2-2. DAY OFF setting
3. TEMPERATURE SET BACK TIMER
Stop mode Stop mode
Operation mode
Stop mode
Operation mode
Preceding day Next day
DAY OFF
Stop mode Stop mode
Operation mode
Stop mode
Operation mode
DAY OFF
Setting day
Preceding day Next daySetting day
Case of SET BACK timer on the Cooling operation.
( Setting temperature :72°F(22°C), SET BACK temperature :78°F(26°C))
SET BACK setting
Operation
temperature
Operation
temperature
78°F
(26°C)
*1
ON OFF OFFON
*1: During the SET BACK function,
the setting temperature is changed.
Change the setting temperature:
72°F(22°C) 75°F(24°C)
72°F
(22°C)
78°F
(26°C)
72°F
(22°C)
75°F
(24°C)

9. ELECTRONIC EXPANSION VALVE CONTROL
The most proper opening of the electronic expansion valve is calculated and controlled under the present
operating condition based on the Table 14.
The compressor frequency, the detected temperature by the discharge temperature sensor,
the indoor heat exchanger sensor, the outdoor heat exchanger sensor, and the outdoor temperature sensor.
The expansion valve is set at 480 pulses 110seconds after the compressor had stopped.
At the time of supplying the power to the outdoor unit, the initialization of the electronic
expansion valve is operated (528 pulses are input to the closing direction).
01-12
( Table 14 : The pulse range of the electronic expansion valve control )
AOU9RLFC
AOU12RLFC
AOU18RLFC
Operation mode Pulse range
Between 60 to 480 pulses.
Between 60 to 480 pulses.
Cooling / Dry mode
Heating mode
Cooling / Dry mode
Heating mode Between 45 to 480 pulses.
Initialization will start after 24 hours pass from the last initialization, and the compressor stops
The compressor won't enter operation status for 2 minutes and 20 seconds after the compressor is stopped,
even if any operation is given.
At the time when the air conditioner is switched from the cooling mode to heating mode, the
compressor is stopped, and the four-way valve is switched in 2 minutes and 20 seconds later after
the compressor stopped.
11. PREVENT TO RESTART FOR 3 MINUTES ( 3 MINUTES ST )
12. FOUR-WAY VALVE EXTENSION SELECT
10. TEST OPERATION CONTROL
[ Wireless remote controller (Option) ]
Under the condition where the air conditioner runs, press the TEST RUN button of the remote control,
and the test operation control mode will appear.
During test running, the operation lamp and timer lamp of the air conditioner body twinkle simultaneously.
[ Wired remote controller ]
If the operation lamp is on, press the START/STOP button to turn it off.
Press the MODE and FAN buttons at the same time for more than two seconds
to start the test operation.
The operation lamp will light up and "o1" will be displayed on the set temperature display.
[ Release ]
Perform the test operation for 60 minutes.
Pressing the START/STOP button will stop the test operation.

14. MANUAL AUTO OPERATION (When using the Wireless RC)
If MANUAL AUTO Button is set, the operation is controlled as shown in Table 16.
If the remote control is lost or battery power dissipated, this function will work without the remote control.
(Table 16 : MANUAL AUTO OPERATION)
01-13
When the power was interrupted by a power failure, etc. during operation, the operation contents
at that time are memorized and when power is recovered, operation is automatically started with
the memorized operation contents.
13. AUTO RESTART
OPERATION MODE Auto changeover
FAN CONT. MODE Auto
TIMER MODE Continuous
SETTING TEMP. 75°F(24°C)
ECONOMY OFF
(No timer setting available)
Manual auto operation
(Table 15 : Operation contents memorized when the power is interrupted)
Operation mode
Set temperature
Set air flow
Set air flow direction
Swing
Economy operation
MIN.Heat operation
Thermistor detected position
Timer mode
Wireless remote
controller
Wired remote controller
(Memory Backup : Disable)
Wired remote controller
(Memory Backup : Enable)
OFF Timer
ON Timer
WEEKLY Timer
Temperature
: Memorize
: Not memorize
*It is necessary to set on the DIP-SW1-No,6 of the wired remote controller, to enable the memory backup.
Refer to the installation manual of wired remote controller for details.
SET BACK Timer
15. COMPRESSOR PREHEATING
16. MIN. (MINIMUM) HEAT OPERATION
MIN. HEAT OPERATION performs as below when pressing MIN. HEAT button or Weekly timer setting on
the remote controller.
Mode Heating
Setting temperature 50°F(10°C)
Fan mode Auto
LED display Economy
Defrost operation Operate as normal
(Table 17 : MIN. HEAT OPERATION)
When the outdoor heat exchanger temperature is lower than 41°F(5°C) and the all operation has
been stopped for 30 minutes, power is applied to the compressor and the compressor is heated.
(By heating the compressor, warm air is quickly discharged when operation is started.)
When operation was started, and when the outdoor heat exchanger temperature rises to 44.6°F(7°C)
or greater, preheating is ended.

01-14
17. ECONOMY OPERATION
The ECONOMY operation functions by pressing ECONOMY button on the remote controller.
At the maximum output, ECONOMY Operation is approximately 70% of normal air conditioner operation
for cooling and heating.
The ECONOMY operation is almost the same operation as below settings.
Mode Cooling/ Dry Heating
Target temperature Setting temp.+2°F(+1°C) Setting temp.-2°F(-1°C)
( Table 18 )
The fan motor for Fresh Air(Field supply) is operated in synchronization with the indoor fan operation as shown in Fig. 10.
The external electrical heater(Field supply) is operated as shown in Fig. 11.
18. FRESH AIR CONTROL
19. EXTERNAL ELECTRICAL HEATER CONTROL
(Fig. 10 : Fresh air control)
(Fig.11 : External electrical heater control)
Operation
Stop
Operation
Stop
Fan motor
(Indoor unit)
Fan motor
(for Fresh Air)
When the room
temperature rises
When the room
temperature drops
Ts : Setting temperature
Heater : OFF
Heater : ON
Heater : OFF
Ts -20°F(10°C)
Ts - 2°F(1°C)
Ts -6°C(3°C)
Ts -24°C(12°C)
When the compressor stop,
External electrical heater is OFF.

01-15
20. DRAIN PUMP OPERATION
1. When the compressor starts, the drain pump starts simultaneously.
2. The drain pump operates continuously for 3 minutes after the compressor is turned off.
3. When the compressor stops by the "Anti- freezing protection", the drain pump is turned off
in 1 hour after the compressor stops.
4. When the water level in the drain pan rises up and then the float switch functions:
The compressor, indoor and outdoor fan motor operation are stopped.
Drain pump operates continuously for 3 minutes after the float switch is turned off.
(Almost condensing water may be drained)
5. When the float switch turns ON continuously for 3 minutes, "FAILURE INDICATION" operates.
(It is necessary to turn off power for release it. )
6. When the float switch turns OFF less than 3 minutes, the unit starts Cooling operation.
1
2
1. When the water level in the drain pan rises up and then the float switch functions:
Drain pump operates continuously for 3 minutes after the float switch is turned off.
(Almost condensing water may be drained)
2. When the float switch turns ON continuously for 3 minutes, "FAILURE INDICATION" operates.
Thereafter, even if the float switch turns OFF, the "FAILURE INDICATION" is not released.
(It is necessary to turn off power for release it. )
During Cooling / Dry mode
3 minutes
ON
OFF
ON
OFF
Compressor
Drain Pump
3 minutes ST
ON
OFF
ON
OFF
ON
OFF
Float Switch
Compressor
Indoor Fan
3 minutes
ON
OFF
ON
OFF
Float Switch
Drain Pump
During HEATING / FAN mode / Stop operation
<Float Switch turns OFF less than 3 minutes>
Less than 3 minutes
The indoor unit fan motor operates after the float switch is turned off.
3
( Fig. 12 : Detail of Drain Pump Operation in Cooling / Dry )
( Fig. 13 : Detail of Drain Pump Operation in Heating )
3 minutes
ON
OFF
Drain Pump

01-16
21. DEFROST OPERATION CONTROL
1. CONDITION OF STARTING THE DEFROST OPERATION
The defrost operation starts as shown in the following Table 19.
2. CONDITION OF THE DEFROST OPERATION COMPLETION
Release Condition
Outdoor heat exchanger temperature sensor value is higher than
+16°C(60.8°F) or Compressor operation time has passed 15 minutes.
(Table 19 : Condition of starting Defrost Operation)
Defrost operation is released when the conditions become as shown in Table 20.
(Table 20 : Defrost Release Condition)
Integrating defrost
If the compressor continuous operation time is less than 10 minutes,
the OFF number of the compressor is counted.
If any defrost operated, the compressor OFF count is cleared.
Normal defrost Compressor integrating operation time
Less than 25 minutes (9/ 12RLFC)
Less than 40 minutes (18RLFC)
More than 25 minutes (9/ 12RLFC)
More than 40 minutes (18RLFC)
Does not operate
Outdoor heat exchanger temp. < 1.4°F(-17°C)
(at outside air temp. > 14°F(-10°C))
Outdoor heat exchanger temp. < Outside air temp.-(12.6°F (7°C))
or Outdoor heat exchanger temp.< -13°F (-25°C)
(at -4°F (-20°C)< Outside air temp.< 14°F (-10°C))
More than 240 minutes
(For continuous operation)
Less than 10 minutes
( For intermittent operation )
Compressor integrating operation time
Outdoor heat exchanger
temperature below 26.6°F(-3°C)
More than 213 minutes
(For continuous operation)
Outdoor heat exchanger
temperature below 23°F(-5°C)
OFF count of the compressor
40 times
=
=
=
=
=
=
Outdoor heat exchanger temp. < Outside air temp.-(12.6°F (7°C))
or Outdoor heat exchanger temp. < -22°F(- 30°C)
(at outside air temp. < -4°F(-20°C))
=