101
Installation and Maintenance
Service Manual
Malfunction of phase
current detection
circuit for compressor
U1
During cooling and drying operation,
compressor will stop while indoor fan will
operate; During heating operation, the
complete unit will stop
Replace outdoor control panel AP1
Malfunction of voltage
dropping for DC
busbar
U3
During cooling and drying operation,
compressor will stop while indoor fan will
operate; During heating operation, the
complete unit will stop
Supply voltage is unstable
Malfunction of
complete units current
detection
U5
During cooling and drying operation, the
compressor will stop while indoor fan will
operate; During heating operating, the
complete unit will stop operation.
Theres circuit malfunction on outdoor units control panel
AP1, please replace the outdoor units control panel AP1.
Cold air prevention
protection
E9
Not the error code. It’s the status code for the operation.
Refrigerant recovery
mode
Fo
Refrigerant recovery. The Serviceman operates it for
maintenance.
Malfunction of
detecting plate(WIFI)
JF
Loads operate normally, while the unit
can’t be normally controlled by APP.
1.Main board of indoor unit is damaged;
2.Detection board is damaged;
3.The connection between indoor unit and detection board is
not good;
Undefined outdoor unit
error
oE
Cool: compressor and outdoor fan stops
operation, while indoor fan operates; Heat:
compressor, outdoor fan and indoor fan
stop operation.
1. Outdoor ambient temperature exceeds the operation range
of unit (eg: less than- 20
o
C or more than 60
o
C for cooling;
more than 30
o
C for heating);
2. Failure startup of compressor?
3. Are wires of compressor not connected tightly?
4. Is compressor damaged?
5. Is main board damaged?
Analysis or processing of some of the malfunction display:
1. Compressor discharge protection
Possible causes: shortage of refrigerant; blockage of air filter; poor ventilation or air flow short pass for condenser; the sys
-
tem has noncondensing gas (such as air, water etc.); blockage of capillary assy (including filter); leakage inside four-way
valve causes incorrect operation; malfunction of compressor; malfunction of protection relay; malfunction of discharge sen-
sor; outdoor temperature too high.
Processing method: refer to the malfunction analysis in the above section.
2. Low voltage overcurrent protection
Possible cause: Sudden drop of supply voltage.
3.Communication malfunction
Processing method: Check if communication signal cable is connected reliably.
4. Sensor open or short circuit
Processing method: Check whether sensor is normal, connected with the corre sponding position on the controller and if
damage of lead wire is found.
5. Compressor over load protection
P
ossible causes: insufficient or too much refrigrant; blockage of capillary and increase of suction temp.; improper running of
compressor, burning in or stuck of bearing, damage of discharge valve; malfunction of protector.
Processing method: adjust refrigerant amount; replace the capillary; replace the compressor; use universal meter to check if
the contactor of compress or is fine when it is not overheated, if not replace the protector.
6. System malfunction
i.e.overload protection.When tube temperature(Check the temperature of outdoor heat exchanger when cooling and check
the temperatur e of indoor heat exchanger when heating) is too high, protection will be activated.
Possible causes: Outdoor temperature is too high when cooling; insufficient outdoor air circulation; refrigerant flow malfunc
-
tion.
please refer to the malfunction analysis in the previous section for handling method .
7. IPM module protection
Processing method:Once the module malfunction happens,if it persists for a long time and can not be selfcanceled, cut off
the power and turn off the unit,and then re-energize the unit again after about 10 min.After repeating the procedure for sever
times, if the malfunction still exists,replace the module.
