Hisense AHM-080HCDSAA - Page 399

378
Troubleshooting
Alarm code
A1
Auxiliary sensor Abnormality (Tow3)
● Alarm code is displayed on the master controller/ the 7-segment of O.U. display PCB / the 7-segment of I.U. PCB1.
● This alarm code is indicated when a short circuit (less than 0.24kΩ) or disconnection (more than 840kΩ) of the thermistor
is detected during the heating or cooling operation. The operation is automatically restarted when the malfunction is
removed.
● Reset the unit to release the alarm.
No
Yes
Yes
No
Is
set enabled on Master
controller?
connected to corresponding
sensor port on I.U.PCB4 as
the same one set on
Master Controller?
thermistor connected
Faulty I.U. PCB1 or I.U.
PCB4 (Check PCBs)
Is sensor port ON
I.U. PCB4 connected to
corresponding sensor port
on I.U.PCB1*?
No
Yes
Yes
No
Yes
No
Auxiliary Sensor A1-A7
in Master Controller
Do not need Tow3
Auxiliary Sensor A1-A7
in Master controller
The thermistor
connected to A1-A7 on
PCB4 must be the same
as set Auxiliary
Sensor A1-A7 in
Master Controller
0
10
20
30
40
50
60
70
80
82
61
46
35
27
20.5
16
12.5
10
8
5.3
3.6
2.5
90
Thermistor
Resistance
(kΩ)
-15 -10 -5 0 5 10 15 20 25 30 35 40 45 50 55 60
Ambient Temperature (
o
C)
Thermistor Characteristics
*I.U. PCB4 connected to corresponding
sensor port on I.U.PCB1
I.U. PCN4 I.U.PCN4 I.U.PCB1
A1
CN1-12
THM8
CN1-11
A2
CN1-8
THM10
CN1-7
A3
CN1-10
THM9
CN1-9
A4
CN2-10
THM6
CN2-9
A5
CN1-6
THM11
CN1-5
A6
CN1-4
THM17
CN1-3
A7
CN1-2
THM18
CN1-1