Fujitsu AOU09RL2, Service Instructions Manual

Page: 29 / 62

Trouble shooting 4
INDOOR UNIT
INDOOR UNIT Error Method:
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)
10.0 12.5 15.71 19.91 25.39 32.67 42.36 55.46 Resistance Value (k )
Temperature
OK
OK
5.316 6.52 8.051 Resistance Value (k )
Temperature
Room temp. sensor error
Indoor unit Controller PCB
Room temperature thermistor
When Room temperature thermistor open or short-circuit is detected.
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.
02-06
25°C
(77°F)
20°C
(68°F)
15°C
(59°F)
10°C
(50°F)
5°C
(41°F)
0°C
(32°F)
-5°C
(23°F)
-10°C
(14°F)
40°C
(104°F)
4.354
45°C
(113°F)
35°C
(95°F)
30°C
(86°F)
THERMISTOR
(ROOM TEMP.)
THERMISTOR
(PIPE)
BLACK
CN4
1
2
3
4
1
2
3
4
BLACK
BLACK
BLACK
Indicate or Display:
Refer to error code table.