7
7
.
.
T
T
R
R
O
O
U
U
B
B
L
L
E
E
S
S
H
H
O
O
O
O
T
T
I
I
N
N
G
G
DC INVERTER AIR CONDITIONER TECHNICAL& SERVICE MANUAL V3.3
98
Fault
code
Fault Description
Possible Reason of Abnormality
How to Deal With
REMARKS
2.The sensor of the expansion valve A（thick
tube）is failure;
3.The sampling circuit is abnormally
2. Replace the sensor for the
expansion valve A(thick tube);
3. Replace the outdoor control board.
&inverter
unitary types
28
Expansion valve B（ thick
tube） sensor fault
1. The wiring of the sensor for the expansion
valve B(thick tube) connect loose;
2.The sensor of the expansion valve B（thick
tube）is failure;
3. The sampling circuit is abnormally
1. Reconnect the wiring of the sensor
for the expansion valve B(thick tube);
2. Replace the sensor for the
expansion valve B(thick tube);
3. Replace the outdoor control board.
FOR
MUTI-SPLIT
outdoor
29
Expansion valve C（ thick
tube） sensor fault
1. The wiring of the sensor for the expansion
valve B(thick tube) connect loose;
2.The sensor of the expansion valve C
（thick tube）is failure;
3. The sampling circuit is abnormally
1. Reconnect the wiring of the sensor
for the expansion valve B(thick tube);
2. Replace the sensor for the
expansion valve C(thick tube);
3. Replace the outdoor control board.
FOR
MUTI-SPLIT
outdoor
30
Expansion valve D （ thick
tube）sensor fault
1. The wiring of the sensor for the expansion
valve B(thick tube) connect loose;
2.The sensor of the expansion valve D（thick
tube）is failure;
3. The sampling circuit is abnormally
1. Reconnect the wiring of the sensor
for the expansion valve B(thick tube);
2. Replace the sensor for the
expansion valve D(thick tube);
3. Replace the outdoor control board.
FOR
MUTI-SPLIT
outdoor
31
The discharge pressure is too
high
1. Overload in cooling;
2. Overload in heating
1. Overload in cooling;
2. Overload in heating
VRF outdoor
32
The suction pressure is too low
fault
1.The refrigerate is not enough for the unit;
2.The expansion valve is failure in heating
mode;
3.The outdoor ambient temperature is too
low in heating mode
1.Check the welding point to confirm
whether it exist the leakage point,
and then add some refrigerate;
2. Replace the expansion valve;
3.The unit should operate within
allowable temperature range.
VRF outdoor
40
high pressure and low
pressure imbalance before
compressor start
1.The wiring of the high/low pressure sensor
connect loose;
2.The wiring of the bypass valve connect
loose;
3. High/low pressure sensor is failure;
4.Bypass coil is failure.
5.Bypass valve is failure.
6.The capillary that connect with bypass
valve blockage
7.The outdoor control board is fault;
1.Reconnect the wiring of high/low
pressure sensor .
2..Reconnect the wiring of the bypass
valve ;
3.Replace pressure sensor.
4.Replace bypass valve coil.
5.Replace bypass coil.
6.Check whether blockage occur.
7.Replace outdoor control board.
VRF outdoor
42
the voltage sensor fault
1.The wiring of the voltage sensor connect
wrong or loose;
2. The voltage sensor is failure;
3. The sampling circuit of the
voltage sensor is failure.
1. Reconnect the wiring of the current
sensor;
2. Replace the voltage sensor;
3. Replace the outdoor control board.
43
High Pressure sensor fault
1.The wiring of the high-pressure pressure
sensor connect loose;
1.Reconnect the wiring of the
high-pressure pressure sensor;
VRF
