Hitachi RAS-5101CH Servicehandbuch Seite 59

TROUBLE-SHOOTING
Operates by setting the service
switch to forces cooling?
Return the service switch to
"Normal".
Set the remote controller to an
operation status and press the ON/
OFF button.
Is the level LO (approx. 0.5V)
between driver IC 2 pin power
relay and OV?
Is the level LO (approx. 0.5V)
between driver IC 2 pin stick
relay and OV?
Is the level LO (approx. 0.5V)
between driver IC 1 pin 'O) (Fan
SSR M) and OV at "MED fan
speed"?
NO
Check the circuit board inside parts.
When checking, carry out a self
diagnosis by indoor indicator lamp.
Check the following parts and replace if faulty
NO
1) Current fuse Remove and check the continuity across.
Check whether the appearance is blackish or not.
The resistance must be infinite. *2
2) Varistor
Thereafter, check the secondary voltage (approx.
3) Transformer 12V AC).
4) Fan motor
protector
(109°C) Continuity across — If there is no
continuity, also check the fan motor and capacitor.
(96°C) Continuity across — If there is no
continuity, check the electric parts and replace if
abnormal.
5) Thermal fuse for
Electric parts
*2 Before checking the veristor, deteach a terminal.
Power relay abnormal Replace Power relay
>
YES
Compressor dose not turn at LO.
y
Stick relay abnormal
Replace Stick relay
YES
-) Fan SSR M abnormal
YES
No "MED fan speed" operation at LO.
*3 Wait for 3 minutes before forced
re-operation by the service switch.
Replace faulty part
ay