Toshiba RAS-4M27S3AV-E Service Manual page 87

Check Outdoor
code LED display
[20]
(Continued)
∗ There is a possibility that it is one of the following errors.
[21]
Confirm LED on outdoor P .C. board to judge which error it is. (1) high-pressure SW system error,
(2) power supply error (Vdc), (3) high-pressure protective operation, (4) case thermo operation.
(Item without special mention indicates part of outdoor unit.)
[PMV error for D room]
Is PMV under correct conditions?
YES
Check temp. sensor of D room indoor unit?
TA sensor, TC sensor
OK
[High pressure SW system error]
High pressure protective operation.
Doesn't high pressure switch
operate?
YES
Are parts of
high pressure switch normal?
YES
Is service valve fully opened?
YES
Reset the power supply and
then do a trial operation according
to the season.
B Cooling operation.
Does cooling outdoor fan
normally operate?
YES
Is there any element
which blocks heat exchanger
of the outdoor unit?
Clogging of heat exchanger
Short circuit
NO
- 87 -
Check and troubleshooting
NO
Error
NO
Is circuit wiring normal?
NO
Parts check
Defective → Replace
NO
Open service valve fully.
B ← Cooling operation
C ← Heating operation
NO
Is there no fan breakage
or coming-off?
YES
YES
FILE NO. SVM-15073
Repair defective position.
Replace defective part.
Correct connector.
Sensor error → Replace.
Check outdoor P .C.B. MCC-5071
and indoor D room P .C. board.
Defect → Replace.
NO
Wiring check,
Correct.
YES
Check IPDU PC board
Defective → Replace
NO
Repair defective position.
Connection of connectors,
IPDU, Fan motor, Wiring.
Elimination of
blocking element
Overcharge of refrigerant/
Clogging/Pipe breakage/
Abnormal overload