Primary Judgement Of Trouble Sources; Role Of Indoor Unit Controller; Display Of Abnormalities And Judgement Of The Abnormal Spots; Judgement From Defective Operation Or Abnormal Operation - Toshiba RAS-10YKH-E Service Manual

9-2. Primary Judgement of Trouble Sources

9-2-1. Role of Indoor Unit Controller

The indoor unit controller receives the operation commands from the remote control and assumes the following
functions.
• Measurement of the draft air temperature of the indoor heat exchanger by using the thermo sensor (TA).
• Louver motor control
• Control of the indoor fan motor operation
• Control of the LED display
• Control of the outdoor unit compressor, 4-WAY VALVE and the outdoor fan motor.

9-2-2. Display of Abnormalities and Judgement of the Abnormal Spots

The indoor unit of this machine observes the operation condition of the air conditioner and displays the contents
of the self-diagnosis as block displays on the display panel of the indoor unit.
A OPERATION display blinking (1 Hz)
B OPERATION display blinking (5 Hz)
C OPERATION display blinking (5 Hz)
D OPERATION display blinking (5 Hz)
E OPERATION display blinking (5 Hz)
F OPERATION, and TIMER Display blinking (5 Hz)
G OPERATION, TIMER and PRE-DEF. display blinking (5 Hz)
H OPERATION, TIMER and PRE-DEF. display blinking (5 Hz)

(1) Judgement from defective operation or abnormal operation

Symptom
Turn off the power once, turn it
No reaction on remote
on again and try to operate the
control operation
remote control again.
The compressor operates.
The outdoor fan does
not rotate
The compressor does not operate.
Table 9-2-1
Block display
Table 9-2-2
Check
Power failure (when power is ON)
Thermo. sensor (TA) short/break
Heat exchanger sensor (TC) short/break
Indoor fan lock, abnormality of indoor fan
Indoor P.C. board failure
Wrong wiring of connecting cable
Thermal fuse is blown
• Gas shortage, other refrigerant cycle trouble
• Heat exchanger sensor open/break/short
• Overload relay or thermostat for compressor trouble
Compressor trouble
Remote control is not possible.
Remote control is possible.
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Description
Primary judgement
The indoor part (including the
remote control) is defective.
OK.
The outdoor part is defective.
(outdoor fan motor)
The inside part is defective.