ERROR CODE: U2 – Power Supply Insufcient 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 insufcient
● 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
OM 1141-3 • MICROTECH UNIT CONTROLLER 152 www.DaikinApplied.com
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