Specifications

Troubleshooting SiUS12-928_A
113 Service Diagnosis
5.9 Anti-icing Function
Remote
Controller
Display
A5
Outdoor Unit LED
Display
A 1 2 3 4
Method of
Malfunction
Detection
During cooling operation, indoor unit icing is detected by checking the temperatures sensed by the
indoor heat exchanger thermistor and the room temperature thermistor that are located in a shut-
down room.
Malfunction
Decision
Conditions
 In cooling operation, the both conditions (A) and (B) are met for 5 minutes.
(A) Room thermistor temperature – Indoor heat exchanger temperature ≥ 10°C (18°F)
(B) Indoor heat exchanger temperature ≤ –1°C (30°F)
 If the error repeats 4 times, the system is shut down.
 Reset condition: Continuous run for about 60 minutes without any other error
Supposed
Causes
 Wrong wiring or piping
 Defective electronic expansion valve
 Short-circuited air
 Defective indoor heat exchanger thermistor
 Defective room temperature thermistor