Reverse Phase, Open Phase - Daikin RXYQ-TA Series Service Manual

Troubleshooting by Error Code

3.55 Reverse Phase, Open Phase

U1
Error Code
Applicable
All outdoor unit models
Models
Method of Error
The phase of each phase are detected by reverse phase detection circuit and right phase or
Detection reverse phase are judged.
Error Decision When a power supply is reverse phase, or T phase is open phase.
Conditions
Supposed
Causes
Troubleshooting
261
Power supply reverse phase
T phase open phase
Defective outdoor unit PCB
Be sure to turn off the power switch before connecting or disconnecting
Caution connectors, or parts may be damaged.
There
is an open
phase at the power
supply (T phase) terminal
section (X1M) of the
outdoor unit.
NO
Operation
is normal if one
phase of power supply
line phase is
replaced.
NO
YES
YES
SiUS341615E
Fix the open phase. Requires
inspection of field power supply
section.
Reverse phase.
Countermeasure of the problem is
completed by phase replacement.
Replace the outdoor unit PCB
(A1P).
Service Diagnosis