Midea V8 VRF Series Service Manual page 76

6.1.28 d16 - Air inlet temperature of IDU is too low in heating mode
Error display
The faulty IDU stops. Other IDUs of the same system: operate normally.
Error impact
ODU of the same system: operate normally.
If the air inlet temperature of the IDU is lower than the set value (See the operating temperature
Error trigger
range set out in the IDU Manual) for 5 min in heating mode
Error recovery
Automatic recovery
Possible cause
See the Troubleshooting section.
Troubleshooting
Note:
1. The inlet air temperature sensor is commonly found in the fresh air IDUs (The sensor code is
defined as T0), and its resistance and temperature characteristics are similar to T1 - return air
temperature sensor. Please refer to the Table of Temperature Sensor Resistance Characteristics
listed in the Maintenance Manual to learn more about the sensor's features.
Digital display
Cause 1: Spo t ch eck th e in let air
temperature and measure the
inle t air tempe rature. If th e p oint
check result is th e same as the
measured result (erro r
is a nor ma l pr ote ction measure
for the uni t. Otherwise, refer to
Cause 2: Remove the plug of the
inle t air tempe rature sen sor from
the ma in control boa rd o f th e
IDU, measure its resistan ce
value, and compare it with the
Table of S ensor Resista nce -
Temperature Characteristics (1).
correspon ds to the resistan ce
value deviates from the actual
d16
inle t air tempe rature by more
Cause 3: The se nso r bo dy
comes into co nta ct with a cold
source, such as low-temperature
conden sed water and cold
surface of a h eat exchange r,
which cau ses the de tected val ue
to b e lo we r than the normal va lue
Cause 4: If th e e rror ca nnot be
cleared after cau ses 1/2/3 have
bee n e limi nated, the ma in control
boa rd o f th e IDU is d amaged
Display position
Panel, display box, and wired controller
1° C), it
cause 2/3/4
If th e tempera ture that
than 5° C, the sen sor is
damag ed.
V8 VRF Indoor Units
It is a normal pro tection
measure fo r the IDU.
When the inlet ai r
temperature exce eds the
set value, the fau lt will b e
cleared
Replace th e in let air
temperature sensor
Elimina te the inte rfer ence
of e xterna l cold source to
the sen sor
Replace th e main control
boa rd o f th e IDU
75