Fujitsu AO G18LBCA Series Original operating manual

SPLIT TYPE
ROOM AIR CONDITIONER
Cassette type
Models Indoor unit Outdoor unit
AUXG18LRLB
AUXG24LRLB
RCG18LRLB
RCG24LRLB
AO*G18LBCA
AO*G24LBCA
INVERTER
SERVICE
INSTRUCTION
R410A
RCG18LRLB
RCG24LRLB

1-6 AIR FLOW DIRECTION CONTROL ......................................................................... 01-09
CONTENTS
1. SPECIFICATIONS
1. DESCRIPTION OF EACH CONTROL OPERATION
1-1 COOLING OPERATION............................................................................................
1-4 AUTO CHANGEOVER OPERATION........................................................................
1-5 INDOOR FAN CONTROL.........................................................................................
1-7 OUTDOOR FAN CONTROL......................................................................................
1-8 COMPRESSOR CONTROL......................................................................................
01-01
1-2 HEATING OPERATION............................................................................................. 01-02
1-3 DRY OPERATION...................................................................................................... 01-03
01-04
01-06
01-10
01-11
1-9 TIMER OPERATION CONTROL............................................................................... 01-12
1-10 ELECTRONIC EXPANSION VALVE CONTROL...................................................... 01-16
1-11 TEST OPERATION CONTROL............................................................................... 01-16
1-12 PREVENT TO START FOR 3 MINUTES (3 MINUTES ST).................................... 01-16
1-13 4-WAY VALVE EXTENSION SELECT.................................................................... 01-16
1-14 AUTO RESTART..................................................................................................... 01-17
1-15 PUMP DOWN.......................................................................................................... 01-17
1-16 COMPRESSOR PREHEATING............................................................................... 01-18
1-17 10°C HEAT OPERATION........................................................................................... 01-18
1-21 VARIOUS PROTECTIONS...................................................................................... 01-22
1-23 HUMAN SENSOR(OPTION) ................................................................................... 01-25
1-20 OFF DEFROST OPERATION CONTROL............................................................... 01-21
1-19 DEFROST OPERATION CONTROL....................................................................... 01-19
1-18 ECONOMY OPERATION........................................................................................ 01-18
1-22 DRAIN PUMP OPERATION ................................................................................... 01-24
2-1 ERROR DISPLAY......................................................................................................
2. TROUBLE SHOOTING
2-2 TROUBLE SHOOTING WITH ERROR CODE..........................................................
2-3 TROUBLE SHOOTING WITH NO ERROR CODE....................................................
2-4 SERVICE PARTS INFORMATION............................................................................
02-01
02-43
02-02
02-49

1 . DESCRIPTION OF EACH
CONTROL OPERATION
R410A
Cassette type
INVERTER

1-1. COOLING OPERATION
1-1-1 COOLING CAPACITY CONTROL
A sensor (room temperature thermistor) built in the indoor unit 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 6.0°C higher than a set temperature,
the compressor operation frequency will attain to maximum performance.
* If the room temperature is 1.0°C lower than a set temperature, the compressor
will be stopped.
* When the room temperature is between +6.0°C to -1.0°C of the setting temperature,
the compressor frequency is controlled within the range shown in Table1.
However, the maximum frequency is limited in the range shown in Fig.1 based on the
fan speed mode and the outdoor temperature.
minimum
frequency
maximum
frequency
10rps 120rps
Hi Me Lo Qu
97rps
97rps
72rps
53rps 37rps 34rps
53rps
53rps
46rps
46rps
49rps 40rps
22rps
34rps
34rps
34rps
A zone
B zone
C zone
D-F zone
Model 18
( Table 1 : Compressor Frequency Range )
( Fig. 1 : Limit of Maximum Frequency based on Outdoor Temperature )
01-01
107rps
107ps
80rps
62rps 47rps 40rps
62rps
62rps
51rps
51rps
56rps 47rps
25rps
40rps
40rps
40rps
A zone
B zone
C zone
D-F zone
Model 24
Fan speed mode
Outdoor air
temperature
A zone
B zone
C zone
D zone
E zone
F zone
When the room
temperature rises
When the room
temperature drops
36°C
32°C
21°C
12°C
2°C
34°C
30°C
19°C
10°C
0°C

01-02
1-2. HEATING OPERATION
A sensor (room temperature thermistor) built in the indoor unit 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 6.0°C than a set temperature,
the compressor operation frequency will attain to maximum performance.
* If the room temperature is higher 1.0°C than a set temperature, the compressor
will be stopped.
* When the room temperature is between +1.0°C to -6.0°C of the setting temperature,
the compressor frequency is controlled within the range shown in Table2.
( Table 2 : Compressor Frequency Range )
minimum
frequency
maximum
frequency
12rps 120rps

1-3. DRY OPERATION
1-3-1 INDOOR UNIT CONTROL
The compressor rotation frequency shall change according to set temperature and room
temperature variation which the room temperature sensor of the indoor unit has detected
as shown in the Table 3.
( Table 3 : Compressor frequency )
( Fig.2 : Compressor Control based on Room Temperature )
01-03
Ts : Setting temperature
Ts+0.5°C
Ts+1.5°C
Operating frequency
34rps
X zone
J zone
0rpsY zone
Room Room
temperature temperature
X zone
J zone
Y zone
Ts-1.5°C
Ts-0.5°C
( Fig.3 : Indoor Fan Control )
10 30 60 360 120 360 120 10 30 (sec)
OFF
S-Lo
Lo
OFF
Setting air flow
Compressor
ON

1-4. AUTO CHANGEOVER OPERATION
01-04
When the air conditioner is set to the Auto mode by remote controller, operation starts in the optimum
mode from among the Heating, Cooling, and Monitoring mode. During operation, the
optimum mode is automatically switched in accordance with temperature changes. The temperature
can be set between 18°C and 30°C in 0.5°C (wireless and 2WIRE remote controller)
Or 1.0°C (3WIRE remote controller) steps.
When operation starts, indoor fan and outdoor fan are operated for around 1 minutes.
Room temperature and outdoor temperature are sensed, and the operation mode is selected
in accordance with the table below. <Monitoring mode>
( Table 4 : Operation mode selection table )
Room temperature (TR)
TR> Ts+2°C
Ts+2°C TR Ts -2°C *Middle zone
TR < Ts -2°C Heating
When the compressor was stopped for 6 consecutive minutes by the temperature control function
after the Cooling or Heating mode was selected at above, operation is switched
to Monitoring and the operation mode is selected again.
When the middle zone is selected on the predetermining of the operation mode, the operation mode
before the changing to the monitor mode is selected.
1
2
3
1
( Fig.4 : Outdoor temperature zone selection )
Cooling
Operation mode
Temperature
25°C and over
25°C under Heating
Cooling
Mode
*If it's Middle zone, operation mode of indoor unit is selected as below.
(1). Same operation mode is selected as outdoor unit.
If outdoor unit is operating in Cooling and Heating mode,
indoor unit will be operated by the same operation mode.
(2). Selected by the outdoor temperature.
If outdoor unit is operating in other than Cooling and Heating mode, indoor unit will be operated
according to the outdoor temperature as below.
TR : Room temperature
Ts : Setting temperature

01-05
START
Room temp.
Ts+2°C?
COOLING OPERATIONHEATING OPERATION
YES
Auto change over is
second or more?
NO
NO
YES
NO
NO
AUTO CHANGEOVER operation flow chart
TS: Setting temperature
Room temp.
Ts -2°C?
Thermostat remains
in OFF state for 6 minutes or
longer?
System stops
or operation command other than
auto changeover operation?
NO
Thermostat remains
in OFF state for 6 minutes or
longer?
System stops
or operation command other than
auto changeover operation?
Middle zone
NO
NO
Operation mode of
outdoor unit : Cooling?
YES
NO
Operation mode of outdoor unit
: Heating?
YES
NO
YES
Outdoor temperature<
25°C?
NO
YES
YES
YES
NO
YES
YES
Operation mode
before the monitor mode is
cooling mode?
Monitor mode

1-5. INDOOR FAN CONTROL
1. Fan speed
( Table 5 : Standard of Indoor Fan Speed )
2. FAN OPERATION
*The following fan speed is a standard value.
The airflow can be switched in 5 steps such as AUTO, QUIET, LOW, MED, HIGH, while the indoor
fan only runs.
01-06
Operation
mode
Air flow
mode
HIGH
MED+
LOW
Heating
Quiet
Cooling
/ FAN
400
300
400
360
340
300
300
300
270
340
380
430
330
430
400
360
330
300
330
270
360
410
HIGH
MED
LOW
Quiet
Soft Quiet
S-Lo
FAN
Dry
3. COOLING 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] ~ [LOW], the indoor motor will run at a constant airflow of [COOL]
operation modes LOW, MED, HIGH,as shown in Table 5.
( Fig.5 : Airflow change - over ( Cooling : AUTO ) )
When the room
temperature rises
When the room
temperature drops
TR : Room temperature
Ts : Setting temperature
TR-Ts > 2°C
=
1°C > TR-Ts
2°C > TR-Ts > 1°C
=
TR-Ts > 2.5°C
=
1.5°C > TR-Ts
2.5°C > TR-Ts > 1.5°C
=
HIGH mode
MED mode
LOW mode
*1
*1 : Contains a condition to the following
When the operation mode is set to AUTO mode
at the start of operation.
When the setting temperature was changed.
When the operation mode was changed to COOLING mode.
When the airflow mode was changed to AUTO mode.
Speed (rpm)
Model 18 Model 24
MED 360 400
Cool air prevention
300 300

4. HEATING OPERATION
Switch the airflow [AUTO], and the indoor fan motor will run according to a room temperature,
as shown in Fig.6.
On the other hand, if switched in [Hi ] ~ [Lo ], the indoor motor will run at a constant airflow
of [HEAT] operation modes Lo, Me, Hi, as shown in Table5.
6. DRY OPERATION
Refer to the table 5.
During the dry mode operation, the fan speed setting can not be changed.
01-07
Indoor heat exchanger
temperature
( Fig.6 : Airflow change - over ( Heating : AUTO ) )
TR-Ts > -1.0°C
=
-2.0°C > TR-Ts
1.0°C > TR-Ts > -2.0°C
=
TR-Ts > -1.5°C
=
-2.5°C > TR-Ts
-1.5°C > TR-Ts > -2.5°C
=
Lo mode
Me mode
Hi mode
5. COOL AIR PREVENTION CONTROL (Heating mode)
The maximum value of the indoor fan speed is set as shown in Fig.7, based on the detected
temperature by the indoor heat exchanger sensor on heating mode.
When the compressor does not operate, the indoor fan motor operates [S-Lo] or [Stop] mode.
( Fig.7 : Cool Air Prevention Control )
Cool air
prevention
S-Lo
42°C
30°C
34°C
Indoor heat exchanger
temperature rises Indoor heat exchanger
temperature drops
Hi
*Me+
or setting fan mode
*Lo
or setting fan mode
*Lo
or setting fan mode
*Lo
or setting fan mode
39°C
37°C
37°C
32°C
24°C
*Lower speed is selected.
42°C
30°C
34°C
Indoor heat exchanger
temperature rises Indoor heat exchanger
temperature drops
Hi
*Me+
or setting fan mode
*Lo
or setting fan mode
39°C
37°C
37°C
32°C
24°C
*Lower speed is selected.
13 min. later