Service Manual
Installation and Maintenance
34
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
Heat
Indicator
Yellow
Indicator
Red
Indicator
Green
Indicator
48
The four-way
valve is
abnormal
U7
OFF 3S
and blink
20 times
If this malfunction occurs
during heating operation,
the complete
unit will stop operation.
1.Supply voltage
is lower than
AC175V;
2.Wiring terminal
4V is loosened or
broken;
3.4V is damaged,
please replace
4V.
49
Zerocrossing
malfunction of
outdoor unit
U9
OFF 3S
and blink
18 times
During cooling
operation,compressor
will stop while indoor
fan will operate; during
heating,the complete
unit will stop operation.
Replace outdoor
control panel AP1
50
Frequency
limiting
(power)
OFF 1S
and blink
13 times
51
Compressor
is opencircuited
OFF 1S
and blink
once
52
The
temperature
for turning
on the unit is
reached
OFF 1S
and blink
8 times
53
Frequency
limiting
(module
temperature)
OFF 1S
and blink
11 times
54 Defrosting
OFF 3S
and blink
once
(during
blinking,
ON 10s
and OFF
0.5s)
OFF 1S
and blink
twice
Defrosting will occur in
heating mode.
Compressor will
operate while indoor fan
will stopoperation.
Its the normal
state
