– 15 –
8-2. Primary Judgement of Trouble Sources
8-2-1. Role of Indoor Unit Controller
The indoor unit controller receives the operation com-
mands from the remote control and assumes the fol-
lowing functions.
•
Measurement of the draft air temperature of the
indoor heat exchanger by using the temperature
sensor (T
A
)
•
Louver motor control
•
Control of the indoor fan motor operation
•
Control of the LED display
•
Control of the outdoor unit compressor and the
outdoor fan motor.
8-2-2. Display of Abnormalities and Judgement
of the Abnormal Spots
The indoor unit of this machine observes the opera-
tion condition of the air conditioner and displays the
contents of the self-diagnosis as block displays on
the display panel of the indoor unit.
Table 8-2
Check
code
–
Check
code
–
System
No reaction on remote control
operation
The outdoor fan does not
rotate
Turn off the power
once, turn it on again
and try to operate the
remote control again.
Primary judgement
The indoor part (including the
remote control) is defective.
O.K.
The outdoor part is defective
(outdoor fan motor)
The inside part is defective.
Remote control is not
possible.
Remote control is
possible.
Check
The compressor operates.
The compressor does not operate.
Block display
OPERATION display flashing (1 Hz)
OPERATION display flashing (5 Hz)
OPERATION display flashing (5 Hz)
OPERATION display flashing (5 Hz)
OPERATION display flashing (5 Hz)
OPERATION and TIMER display flashing
(5 Hz)
OPERATION, TIMER and FAN ONLY display
flashing (5 Hz)
OPERATION, TIMER and FAN ONLY display
flashing (5 Hz)
Self-diagnosis
Power failure (When power is on)
Temperature sensor (T
A
) short/break
Heat exchanger sensor (T
C
) short/break
Indoor fan lock, abnormality of indoor fan,
IC03, D15 short/break
Indoor PC board failure
• Thermal fuse is blown
(Indoor fan motor is overheat)
• Gas shortage, other refrigerant cycle
trouble
• Heat exchanger sensor open/short/break
• Overload relay trouble
Compressor trouble
(1) Judgement from defective operation or abnormal operation
Table 8-3