Daikin GYEQ20AN Service Manual page 161

SiAUY361411EA
22
Indoor Unit Electronic Expansion Valve Failure
Sub-code 0: During cooling operation, the following conditions continue for 20 minutes: 1) SHS1 is equal to or
Description
of the failure
Indoor unit temperature sensor failure; indoor unit electronic expansion valve failure;
Possible
causes high/low-side pressure sensor failure; intake air temperature sensor failure; harness failure;
of the failure
main circuit board failure; indoor unit filter/heat exchanger fouled; refrigerant overcharged
Flow chart
Are Indoor Unit Filter
and Heat Exchanger
Free From Dirt?
YES
Is Indoor Unit
Electronic Expansion Valve
Operating Normally?
YES
Are Indoor Unit
Temperature Sensors
Operating Normally?
YES
Are Sensors Connected
Properly To Main Circuit
Board's Harness?
YES
Is High/Low-Side Pressure
Sensor Operating Normally?
YES
Are Intake Air Temperature
Sensors Operating Normally?
YES
Are Discharge Temperature
Sensors Operating Normally?
YES
Check whether Refrigerant is
not overcharge.
Troubleshooting
lower than 2°C; 2) SHS2 is equal to or lower than 2°C; 3) the high-side pressure minus low-side
pressure is equal to or higher than 1000 kPa.
NO
Check Indoor Unit Filter
and Heat Exchanger.
NO
Check Electronic
Expansion Valve.
NO
Check Indoor Unit
Temperature Sensors.
NO
Check Electrical
NO
Check High/Low-Side
Pressure Sensor.
NO
Check Intake Air
Temperature Sensors.
NO
Check Discharge
Temperature Sensors.
Wiring System.
025888-00EN03
Flow Charts for Troubleshooting
Error
code
H6
150