1-53
TROUBLESHOOTING
“RUN” light flickers and “ALARM” is indicated on the remote control switch.
The unit No., alarm code and the unit code is alternately indicated on the set temperature section, or
the unit No. and alarm code are indicated on the display of the outdoor unit PCB. (*1)
If abnormality with the thermistor is found, check all the thermistors as shown below.
This alarm code is indicated when the thermistor is short-circuited (less than 0.9 k
Ω
) or cut (greater
than 2,350 k
Ω
) during running.
Alarm
Code
Abnormality of Thermistor for Discharge Gas
Temperature on the Top of Compressor Chamber
Cause
Check Item
Action
(Turn OFF Main Switch)
Phenomenon
Faulty Discharge
Gas Thermistor
Check resistance.
Replace thermistor
if faulty.
Fault
Check wiring to PCB.
Repair wiring and
connections.
Incorrect Connection
Replace PCB and
check operation.
Replace PCB if faulty.
Faulty PCB
Check setting of
DSW2 on PCB1.
Correctly set
DSW2 on PCB1.
Incorrect Setting of DSW2 on PCB1
Yes
Yes
Set DSW2 on PCB1
correctly.
No
Connect them.
No
Faulty Thermistor.
No
Position of Thermistor
(*1) Indication on the display
of the outdoor unit PCB.
Faulty PCB1
Is the setting of DSW2
on PCB1 right?
Are thermistors, THM8,
THM9, THM12 and
THM13 connected to
THM8(TD1), THM9(TD2),
THM12(TD3) and
THM13(TD4)?
Yes
Is resistance of
THM8, THM9, THM12
and THM13 same with
characteristic in right
figure?
1 2 3 Faulty TD1
2 2 3 Faulty TD2
3 2 3 Faulty TD3
4 2 3 Faulty TD4
THM8 (TD1)
for Inverter Drive
RAS-5FSG, RAS-5FS3
THM8 (TD1)
for Inverter
Drive
RAS-8FSG, RAS-8FS3
RAS-10FSG, RAS-10FS3
RAS-8FXG, RAS-8FX3
RAS-10FXG, RAS-10FX3
THM9 (TD2)
for Constant
Speed Drive
THM8 (TD1)
for Inverter
Drive
RAS-16FSG, RAS-16FS3
THM9 (TD2)
RAS-20FSG,
RAS-20FS3
RAS-24FSG1,
RAS-24FS5,
RAS-30FSG1,
RAS-30FS5
THM12 (TD3)
THM13 (TD4)
20, 24, 30HP
only
for Constant Speed Drive
200
100
R25=200k
Ω
B=3920k
72.3
14.2
8.32
0
25
50
100 120 150
Ambient Temperature (
o
C)
Resistance
of Thermistor
(k
Ω
)
Characteristics of Thermistor
