Refrigerant Shortage (Alert) - Daikin ZQG71~140L7V1B Service Manual

Troubleshooting by Remote Controller

4.29 Refrigerant Shortage (Alert)

U0
Remote
Controller
Display
Applicable
RZQG
Models
Method of Error
Refrigerant shortage is detected according to the electronic expansion valve opening degree
Detection and measured temperatures and pressures.
Error Decision
(In cooling operation)
Conditions When the electronic expansion valve opens fully and low pressure is below 0.25 MPa
continuously for 30 seconds.
(In heating operation)
When the electronic expansion valve opens fully and the suction superheat is large (more than
20°C) continuously for 60 seconds.
 Even if error occurs, operation will continue.
Supposed  Stop valve is not opened
Causes  Insufficient refrigerant amount
 Clogged refrigerant piping system
Troubleshooting
Caution
Be sure to turn off power switch before connect or disconnect connector, or parts damage may be occurred.
Is the refrigerant
amount appropriate?
YES
Note:
 Refrigerant shortage alarm is indicated but operation continues.
CHECK 9 Refer to P.202.
176
NO
ESIE12-06
Collect refrigerant. After vacuum
drying is complete, charge an
appropriate amount of
refrigerant.
CHECK 9
Check the refrigerant piping
system for clogging.
Service Diagnosis