Electronic Expansion Valve Coil Abnormality, Dust Clogging - Daikin RXSQ24TAVJU Service Manual

Troubleshooting by Error Code
4.15 Electronic Expansion Valve Coil Abnormality, Dust
Clogging
A9
Error Code
Applicable All indoor units
Models
Method of Error Electronic expansion valve coil conditions are checked via microcomputer.
The electronic expansion valve main body is checked for dust clogging via microcomputer.
Detection
Error Decision Pin input for electronic expansion valve coil is abnormal when initializing microcomputer.
Either of the following conditions is seen/caused/occurs while the unit stops operation.
Conditions
R1T: temperature of suction air
R2T: temperature of liquid pipe of heat exchanger
Supposed
Causes
Troubleshooting
CHECK 18
179
R1T – R2T > 8°C (14.4°F)
R2T shows fixed degrees or below.
Defective electronic expansion valve coil
Defective indoor unit main PCB
Defective relay cables
Be sure to turn off the power switch before connecting or disconnecting
Caution connectors, or parts may be damaged.
Power is supplied.
YES
Electronic
expansion valve is
connected to X7A
of indoor unit
PCB.
YES
Check
of electronic
expansion valve coil
indicates normal.
CHECK 18
YES
Relay cables short
circuit or
disconnected.
NO
Refer to page 273.
NO
NO
NO
YES
SiUS331708EA
Replace the electronic expansion
valve main body.
Shut the power supply OFF after
connection and then restart.
Replace the electronic expansion
valve coil.
Replace the relay cables.
When restarting the operation after
shutting the power supply OFF
does not work, replace the indoor
unit main PCB (A1P).
Service Diagnosis