Fujitsu AB Series A18LATN User Manual

Trouble shooting 4
INDOOR UNIT
INDOOR UNIT Error Method:
Indicate or Display:
Outdoor Unit : No indication
ERROR CODE : E : 04
Detective Actuators:
Detective details:
Forecast of Cause :
Check Point 2 :
31.7
35°C
39.6
30°C
49.762.980.3103134176Resistance Value (k )
25°C20°C15°C10°C5°C0°C
Temperature
OKOK
OK
17.120.825.6Resistance Value (k )
50°C45°C40°C
Temperature
Indoor Heat Exchanger Temperature
Sensor Error
Indoor Unit Controller PCB Circuit
Heat Exchanger Temperature Thermistor
When Heat Exchanger Temperature Thermistor open or short-circuit is
detected at power ON.
1. Connector connection failure 2.Thermistor failure 3. Controller PCB failure
Check Point 1 : Check connection of Connector
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.
Check Point 2 : Remove connector and check Thermistor resistance value
Thermistor Characteristics (Approx. value)
If Thermistor is either open or shorted, replace it and reset the power.
Check Point 3 : Check voltage of Controller PCB (DC5.0V)
Make sure circuit diagram of indoor unit and check terminal voltage at Thermistor (DC5.0V)
If the voltage does not appear, replace Controller PCB.
07-07
THERMISTOR
(PIPE TEMP.)
THERMISTOR
(ROOM TEMP.)
GRAY GRAY BLACK BLACK
CN5 CN7 CN8
1 2 1 2
1 2 1 21 2

Fujitsu AB Series A18LATN Specifications

General

Brand	Fujitsu
Model	AB Series A18LATN
Category	Air Conditioner
Language	English