Si10-417
Troubleshooting
Service Diagnosis
37
5.2.2 Freeze-up Protection Control
Remote
Controller
Display
A5
Outdoor
Unit LED
Display
A
5
1
4
2
1
3
4
4
4
Method of
Malfunction
Detection
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.
Malfunction
Decision
Conditions
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>
Supposed
Causes
Wrong wiring or piping
Ev malfunctioning in each room
Short-circuit
Indoor unit heat exchanger thermistor defective
Indoor unit thermistor defective
Si10-417.fm Page 37 Wednesday, September 22, 2004 6:38 PM
