TROUBLESHOOTING
13-2 Service Manual – YBZE DCI 1-A.1 GB
13.1.3 Fault Code display from ODU
The ODU can not show fault directly, can only know whether there is fault status by Communication LED.
(Fault status – LED ON 1sec, OFF 1sec. )
13.1.4 Fault Code display from IDU
If the malfunction still exists 4min later after stop of unit due to compressor protection, error code will be
directly displayed though indoor display. In other situations, fault code can be displayed by pressing
LIGHT button 6 times within 4s.
Fault code can be displayed on 2*7 segments or by the LEDs blinking (OFF for 3s and then with certain
blinking as following)
1. Refrigerant was superabundant
2. Poor heat exchange (including blockage
and bad radiating environment )
3. Too high ambient temperature
Indoor coil defrost Protection
1. Poor air-return in indoor unit
2. Fan speed is abnormal
3. Evaporator is dirty.
Compressor over Heating
Protection
1. EEV connection problem or damage
2. Refrigerant leakage
3. Poor heat exchange
AC Over current protection
1. Supply voltage is unstable
2. Supply voltage is too low and load is too
high
Communication malfunction
1. Wiring mistakes
2. IDU or ODU PCB problem
Mode conflict to other IDU
Indoor coil/Outdoor coil over
heating protection
1. Too high ambient temperature
2. Poor heat exchange (including blockage
and bad radiating environment )
No feedback of indoor motor
1. IFAN motor damaged
2. IFAN motor blocked
3. IDU PCB problem
Malfunction protection of
jumper cap
Poor connection of the jumper on indoor
PCB.
Zero-crossing protection (IDU)
1. IFAN motor damaged
2. Zero-crossing circuit damaged on IDU
PCB
1. Senor was broken or damaged
2. PCB temperature detection circuit has
problem
1. AC input voltage is too high.
2. Reactor has problem
3. ODU PCB has problem
1. Senor was broken or damaged
2. PCB temperature detection circuit has
problem
Compressor overload
protection
1. EEV connection problem or damaged
2. Refrigerant leakage
3. OLP damaged
1. Abnormal power input voltage.