Lennox VRF VEC027N432U, User Manual, Page: 31 / 36

DC Inverter Multi VRF System
27
(2) Following circumstances are not malfunctions.
Malfunction Reason
Unit doesn’t run.
Unit starts up immediately after it is
turned off.
Overload protection switch makes it run after a 3-min
delay.
Power is just turned on. Standby operation lasts for about 1min.
Mist comes from
the unit.
Under cooling. Indoor air with high humidity is cooled rapidly.
Noise is emitted.
Slight cracking sound is heard when unit
is just turned on.
It is the noise when electronic expansion valve is
initialized.
There is consecutive sound when
cooling.
It is the sound for gas refrigerant flowing in the unit.
There is sound when unit starts or stops. It is the sound when gas refrigerant stops flowing.
There is slight and consecutive sound
when unit is running or after running.
This is the sound of drainage operation.
Cracking sound is heard when unit is
running or after running.
This is the sound caused by the expansion of panel
and other parts of the unit due to temperature
change.
Unit blows out
dust.
Unit starts up after not operating for a
long time.
Dust in indoor unit is blown out.
Unit emits odor. Under operation. Unit absorbs the room odor and then blows it out.
7 Error Indication
Inquiry method of error indication: combine division symbol and content symbol to check the
corresponding error.
Indoor:
Error Code Content Error Code Content
L0 Malfunction of IDU (uniform) d1 Indoor PCB is poor
L1 Protection of indoor fan d3
Malfunction of ambient temperature
sensor
L2 Auxiliary heating protection d4
Malfunction of entry-tube temperature
sensor
L3 Water-full protection d5
Malfunction of middle temperature
sensor
L4
Abnormal power supply for wired
controller
d6
Malfunction of exit-tube temperature
sensor
L5 Freeze prevention protection d7 Malfunction of humidity sensor
L6 Mode shock d9 Malfunction of jumper cap
L7 No main IDU dA Web address of IDU is abnormal
L8 Power supply is insufficient dH PCB of wired controller is abnormal
L9
1-to-more: number of IDU is
inconsistent
dC
Setting capacity of DIP switch code is
abnormal
LA t1-to-more: IDU series is inconsistent dL
Malfunction of air outlet temperature
sensor
LH
Alarm due to bad air quality (Fresh air
unit)
dE Malfunction of indoor CO
2
sensor
LC IDU is not matching with outdoor unit db Debugging status
Outdoor:
Error Code Content Error Code Content
E0 Malfunction of ODU (uniform) F0 Main board of ODU is poor
E1 High-pressure protection F1 Malfunction of high-pressure sensor
E2 Discharge low-temperature rotection F3 Malfunction of low-pressure sensor
E3 Low-pressure protection F5
Malfunction of discharge temperature
sensor of compressor 1