Hitachi RAS-35FH6 - OH Thermistor and Overload Cut Troubleshooting

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LD301 blinks 6 times.
The temperature at the
OH thermistor rises.
Is the thermistor circuit
normal?
Replace parts in the
thermistor circuit.
LD301 blinks 5 times.
Overload lower limit cut.
Replace the main P.W.B.
Check to see if the refrigerating cycle is defective.
Check the indoor unit for clogged heat exchanger or filter.
Check the outdoor unit for defective shielding.
LD301 blinks 4 times.
Failure of switching.
Is the 15V power supply
output normal?
(Power P.W.B. display)
Is the intelligent power
module (IPM) normal?
(Inverter section)
The intelligent power module
may be defective.
Replace the main P.W.B.
See “System Power
Module Diagnosis”.
With CN3 and CN4
disconnected, is the 15V
output between “15V” and
”15-0V” on the power
P.W.B.?
Replace the power P.W.B.
LD301 blinks 3 times.
Abnormal low speed.
Yes
Yes
Yes
Yes
Yes
Yes
Yes No
No
No
No
No
No
No
06K134_RAS_35YH6_061-082_E 10/25/06, 4:08 PM81