Hitachi RAS-25CNH1 Service Manual page 85

CHECKING THE INDOOR/OUTDOOR UNIT ELECTRICAL PARTS AND REFRIGERATING CYCLE
[ MODEL RAS-25CNH11 / RAC-25CNH11 ]
Does the timer or dehumidifying lamp on
the indoor unit blink?
Set to room temperature 16°C in the
cooling mode or to 32°C in the heating
mode, and press the start/stop button.
Does the operation lamp on the indoor unit
start to light or blink?
Is the compressor in the outdoor unit
operating?
Yes
Remove the outdoor unit cover
and electrical parts cover, and
check self-diagnosis lamp LD301.
A B C
Does LD301 blink one time?
* Repeats 0.25-second on and
2-second off.
Blinking other
than one-time
See Outdoor unit self-
diagnosis lamp lighting mode.
Check the refrigerating cycle.
No
Yes
No
Service switch
LD301
LD302
LD303
D
One-time blinking
Set the service switch on the
outdoor unit to "cooling". Does
the compressor operate? (After
checking, be sure to return the
service switch to "normal".)
Check the outdoor electrical parts.
Timer
lamp
See "Troubleshooting when the timer lamp
blinks".
Check the outdoor electrical parts.
Dehumidifying
lamp
Remove the decorative cover and electrical
parts cover and check the pin voltages of
CN3 (brown and red wires).
Pin : +35 V, pin
5
No
Is approx. 35V DC being generated? Is the
polarity correct?
No
Check to see whether the F-
cable is connected incorrectly
or disconnected.
Normal
Yes
No
– 94 –
: 0V
3
D101
+ –
Yes
Check the indoor electrical parts.