Daikin GYEQ20AN Service Manual page 156

Flow Charts for Troubleshooting
18
Compressor Oil Detected Too Low
Sub-code 0: An empty oil separator has been detected.
Sub-code 2: While oil separator heating control is being performed, SH01 or SH02 whichever is lower stays
Description
of the failure
Sub-code 3: SH01 or SH02 whichever is lower stays equal to or lower than 10°C for 5 minutes, or stays equal
Compressor oil leak; compressor failure; oil return pipe clogged; high-side pressure sensor failure;
low-side pressure sensor failure; intake air temperature sensor failure; discharge temperature sensor failure;
Possible
oil temperature sensor failure; SV failure; main circuit board failure; outdoor/indoor unit EV failure;
causes
check valve failure; four-way valve failure; refrigerant overcharged; indoor unit fan failure; heater failure;
of the failure
indoor unit filter/heat exchanger fouled; power supply failure; refrigerant recharging incorrect;
energization time too short; power-ON start/power-OFF stop; BS unit failure
Flow chart
When Sub-code is 0
Is Unit Free From
Compressor Oil Leaks?
YES
Is EV operating Normally?
YES
Is SV Operating Normally?
YES
Are Compressors Operating
Normally? Is There Sufficient
Refrigerating Machine Oil In
Compressor Case?
YES
Is High-Side Pressure Sensor
Operating Normally?
YES
Is Low-Side Pressure Sensor
Operating Normally?
YES
Are Oil Temperature Sensors
Operating Normally?
YES
Are Intake Air Temperature
Sensors Operating Normally?
YES
Check Discharge
Temperature Sensors.
145
equal to or lower than 5°C for 40 minutes.
to or lower than 5°C for 2 minutes, or stays equal to or lower than 2°C for 10 seconds after 10
minutes or longer have elapsed after startup.
NO
Check Compressor Oil Leaks.
NO
Please take care with the tele
controller connection.
NO
NO
Check Compressors.
Check Oil return Pipe.
Make sure that the indoor unit is
free from communication pipe
clogging and refrigerating machine
oil accumulation.
NO
Check High-Side
Pressure Sensor.
NO
Check Low-Side
Pressure Sensor.
NO
Check Oil Temperature
NO
Check Intake Air
Temperature Sensors.
Check EVs.
Check SVs.
Sensors.
025881-01E01
SiAUY361411EA
Error
FH
code
Troubleshooting