46
Installation and Maintenance
Service Manual
NO.
Malfunction
Name
Display Method of Indoor Unit
Display Method of Outdoor Unit
A/C status
Possible Causes
Dual-8
Code
Display
Indicator Display (during
blinking, ON 0.5s and OFF
0.5s)
Indicator has 3 kinds of display
status and during blinking, ON
0.5s and OFF 0.5s
Operation
Indicator
Cool
Indicator
Heating
Indicator
Yellow
Indicator
Red
Indicator
Green
Indicator
53
Normal
communica-
tion
continously
54
55
Defrosting
OFF 3S
and blink
once
(during
blinking,
ON 10s
and OFF
0.5s)
OFF 3S
and blink
twice
Defrosting will occur in
heating
mode. Compressor will
operate
while indoor fan will stop
operation.
Its the normal state
U8
Flash 17
times
every 3s
Operation
of remote
controller or
control
panel is
available,
but the unit
won’t act.
1. Discharging speed of
capacitor is slow, which lead
to wrong judgement of
controller.
Zero-crossing detection
circuit of main board is
abnormal
Refer to maintenance flowchart
Refer to the malfunction analysis
Zero-crossing
inspection
circuit malfun-
ction of the
IDU fan motor
56
Malfunction
of detecting
plate(WIFI )
JF