OM 1263 • MICROTECH UNIT CONTROLLER 98 www .DaikinApplied .com
Troubleshooting
ERROR CODE:
U2 – Power Supply Insufficient or Instantaneous Failure
Remote
Controller
Display
U2
Method of
Malfunction
Detection
Detection of voltage of main circuit capacitor built in the inverter and power supply voltage .
Malfunction
Decision
Condition
When the voltage aforementioned is not less than 780V or not more than 320V, or when
the current-limiting voltage does not reach 200V or more or exceeds 740V .
For 230V units: When the voltage aforementioned is not more than 190V .
Supposed
Causes
● Power supply insufficient
●
Instantaneous power failure
●
Open phase
●
Defect of inverter PC board
●
Defect of outdoor control PC board
●
Main circuit wiring defect
●
Faulty compressor
●
Faulty fan motor
●
Faulty connection of signal cable