Minutes - Hitachi RAS-25JX4 Service Manual

TROUBLESHOOTING WHEN TIMER LAMP BLINKS.
MODEL RAS-25JX4, RAS-35JX4
Perform troubleshooting according to the number of times the indoor timer lamp.
SELF-DIAGNOSIS LIGHTING MODE
MODEL RAS-25JX4, RAS-35JX4
No. Blinking of Timer lamp
1
2 sec.
2
2 sec.
3
2 sec.
4
5
6
1
7
2
8
2
( Lights for 0.35 sec. at interval of 0.35 sec..)
Reversing valve defective
When the indoor heat exchanger
1 time temperature is too low in the
heating mode or it is too high in the
cooling mode.
Outdoor unit is under forced
operation
2 times
When the outdoor unit is in forced
operation or balancing operation
after forced operation
Indoor/outdoor interface defective
3 times
When the interface signal from the
outdoor unit is interrupted.
Room thermistor or heat exchanger
thermistor is faulty
When room thermistor or heat
9 times
2 sec.
exchanger thermistor is opened
circuit or short circuit.
Over-current detection at the DC fan
motor
10 times
2 sec. when over-current is detected at the
DC fan motor of the indoor unit.
IC401 data reading error
13 times When data read from IC401 is
2 sec.
incorrect.
Ventilation fan abnormal
Ventilation fan motor does not rotate
16 times
2 sec.
Dirt sensor abnormal
Dirt sensor disconnection or short
17 times
2 sec.
ckt.
Reason for indication
91
Possible cause
(1) Reversing valve defective
(2) Heat exchanger thermistor
disconnected
(only in the heating mode)
(Note)
The malfunction mode is entered the
3rd time this abnormal indication
appears (read every 3 minutes).
Electrical parts in the outdoor unit
(1) Indoor interface circuit
(2) Outdoor interface circuit
(1) Room thermistor
(2) Heat exchanger thermistor
(1) Indoor fan locked
(2) Indoor fan motor
(3) Indoor control P.W.B.
IC401 abnormal
(1) Ventilation fan locked
(2) Ventilation fan motor
(3) Indoor control P.W.B.
(1) Dirt sensor circuit
(2) Disconnection of dirt sensor
connector or lead wire