Troubleshooting 6
INDOOR UNIT Error Method:
Detective actuators:
Detective details:
Forecast of cause :
Check Point 2 :
OK
OK
OK
Indoor unit heat-exchanger sensor error
Indoor unit controller PCB
Heat Ex. temperature thermistor
When heat-exchanger temperature thermistor
open or short-circuit is detected.
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.
02-10
THERMISTOR
(ROOM TEMP.)
THERMISTOR
(PIPE)
BLACK
CN4
1
2
3
4
1
2
3
4
BLACK
BLACK
BLACK
62.9
102.1
131.4
170.7
223.3
295.1
Resistance Value (k )
Temperature
17.11
25.8
39.78
Resistance Value (k )
Temperature
20°C
10°C
5°C
0°C
-5°C
-10°C
50°C
11.6
60°C
10.36
63°C
40°C
30°C
