Daikin AT12BV1LS Pocket Manual page 38

Si10-417
5.2.2 Freeze-up Protection Control
Remote
Controller
Display
Outdoor
Unit LED
Display
Method of
Malfunction
Detection
Malfunction
Decision
Conditions
Supposed
Causes
Service Diagnosis
A5
A 1 2
5 4
Indoor unit icing, during cooling operation, is detected by
checking the temperatures sensed by the indoor unit
heat exchanger thermistor and room temperature
thermistor that are located in a shut-down room.
In the cooling mode, the following conditions (A) and (B)
are kept together for 5 minutes.
(A) Indoor unit heat exchanger temperature ≤ –1°C
(B) Indoor unit heat exchanger temperature ≤ Room
temperature –10°C
If the indoor unit icing protector is activated four times
straight, the system will be shut down.
(The 4-time counter will reset itself if any of the
following errors does not occur during the compressor
running time (total time): OL, radiation fin temperature
rise, gas shortage, and compressor startup.)
<Total 60 minutes>
Wrong wiring or piping
Ev malfunctioning in each room
Short-circuit
Indoor unit heat exchanger thermistor defective
Indoor unit thermistor defective
3 4
1 4 4
Troubleshooting
37