SiUS12-928_B Troubleshooting for Outdoor Unit
Service Diagnosis 170
6.11 Four Way Valve Abnormality (18 Class Only)
Remote
Controller
Display
EA
Outdoor Unit LED
Display
A j 1 i 2 h 3 h 4 h
Method of
Malfunction
Detection
The liquid pipe thermistor and the outdoor heat exchanger thermistor are checked to see if they
function within their normal ranges in the operating mode.
Malfunction
Decision
Conditions
Either of the following conditions occurs 6 minutes after the compressor has started.
Cooling operation
The lowest liquid pipe temperature among the rooms in operation –Tde > 5°C (41°F)
Heating operation
The highest liquid pipe temperature among the rooms in operation –Tde < 0°C (32°F)
Tde: outdoor heat exchanger temperature
Supposed
Causes
Poor connector contact
Defective thermistor
Defective outdoor unit PCB
Defective four-
way valve, coil, or harness
Foreign substance mixed in refrigerant
To Next Page
Loading...