Fujitsu AB Series A18LATN, Service Instruction

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Trouble shooting 3
INDOOR UNIT
INDOOR UNIT Error Method:
Indicate or Display:
Outdoor Unit : No indication
ERROR CODE : E : 02
Detective Actuators: Detective details:
Forecast of Cause :
Check Point 2 : Check Point 2 : Remove connector and check Thermistor resistance value
Check Point 1 : Check connection of Connector
Check Point 3 : Check Point 3 : Check voltage of Controller PCB (DC5.0V)
6.51
35°C
8.04
30°C
10.0 12.5 15.8 20.2 25.9 33.6 Resistance Value (k )
25°C 20°C 15°C 10°C 5°C 0°C
Temperature
OK
OK
3.59 4.35 5.30 Resistance Value (k )
50°C 45°C 40°C
Temperature
THERMISTOR
(PIPE TEMP.)
THERMISTOR
(ROOM TEMP.)
G
R
A
Y
G
R
A
Y
B
LA
C
K
B
LA
C
K
CN5 CN7 CN8
1 2 1 2
1 2 1 2
Room Temperature Sensor Error
Indoor Unit Controller PCB Circuit
Room Temperature Thermistor
When Room Temperature Thermistor open or short-circuit is
detected at power ON.
1. Connector connection failure 2.Thermistor failure 3. Controller PCB failure
Check if connector is removed.
Check erroneous connection.
Check if thermistor cable is open.
>>Upon correcting the removed connector or mis-wiring, reset the power.
Thermistor Characteristics (Approx. value)
If Thermistor is either open or shorted, replace it and reset the power.
Make sure circuit diagram of indoor unit and check terminal voltage at Thermistor (DC5.0V)
If the voltage does not appear, replace Controller PCB.
07-06
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