30
Installation and Maintenance
Service Manual
6
High pressure
protection
E1
OFF 3S and
blinks once
During cooling and drying
operation, except indoor
fan operates, all loads stop
operation. During heating
operation, if it is inverter unit,
the complete unit stops; if it is
floor standing unit, the complete
unit stops and operation of
remote controller or controller is
unavailable.
1. The main board and the display panel are not connected well.
2. The OVC terminal on main board is not connected well with the high
pressure switch on the complete unit.
3. The wiring of high pressure switch is loosened.
4. Refrigerant is superabundant;
5. Poor heat exchange (including blocked heat exchanger and bad
radiating environment );
6. Ambient temperature is too high; (if it is 3-phase unit, the high
pressure protection may be caused by overcurrent protection due to
this reason)
7. The supply voltage is abnormal (if it is 3-phase unit, the high pressure
protection may be caused by overcurrent protection due to this reason)
8. The air intake and air discharge at indoor / outdoor heat exchanger
are not smooth. The air cycle is short circuited.
9. Filter and heat exchange fins of indoor/outdoor units are blocked.
10. The system pipeline is blocked.
11. The gas valve and liquid valve for outdoor unit are not completely
opened.
12. The OVC input is at high level.
7
High discharge
temperature
protection of
compressor
E4
OFF 3S and
blinks 4 times
(inverter
unit); running
indicator
blinks (non-
inverterfloor
standing unit);
As for other
types of units,
please refer
to the detailed
function
requirement.
During cooling and drying
operation, compressor and
outdoor fan stop while indoor
fan operates. During heating
operation,all loads stop.
1. Abnormal system (e.g.: blockage, etc)
2. Abnormal rotation speed of outdoor motor (cooling )
3. Abnormal air intake (cooling)
4. System is normal, but the compressor discharge temperature sensor
is abnormal or poorly contacted.
8
Overcurrent
protection
E5
OFF 3S and
blinks 5 times
During cooling and drying
operation, compressor and
outdoor fan stop while indoor
fan operates. During heating
operation, all loads stop.
1. Unstable supply voltage. Normal fluctuation shall be within 10% of
the rated voltage on the nameplate.
2. Supply voltage is too low and load is too high.
3. Measure the current of live wire on main board. If the current
isn’t higher than the overcurrent protection value, please check the
controller.
4. The indoor and outdoor heat exchangers are too dirty, or the air inlet
and air outlet are blocked.
5. The fan motor is not running. Abnormal fan speed: fan speed is too
low or the fan doesn’t run
6. The compressor is not running normally. There is abnormal sound, oil
leakage or the temperature of the shell is too high, etc.
7. There’s blockage in the system
（
filth blockage, ice plug, greasy
blockage, Y-valve hasn’t been opened completely
）
9
Communication
malfunction
E6
OFF 3S and
blinks 6 times
During cooling operation,
compressor stops while indoor
fan motor operates. During
heating operation, the complete
unit stops.
1. The communication line is not connected tightly or poorly contacted.
Poor contact of any line may cause communication malfunction.
2. The match between main board and display panel is incorrect.
Indoor and outdoor unit boards are matched incorrectly.
3. Incorrect wire connection.
4. Controller is damaged.
