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Error mode detected by outdoor unit (3)
Operation of diagnostic function
Check
code A
Check
code B
Cause of operation
Status of air
conditioner
Condition
Judgment and measures
Inverter over-current protective
circuit operates. (For a short time)
All stop
Displayed when
error is detected
1. Inverter immediately stops even if restarted.
• Compressor rare short
2. Check IPDU.
• Cabling error
Error on current detection circuit
• Current value is high at AC side
even while compressor stops.
• Phase of power supply is missed.
All stop
Displayed when
error is detected
1. Compressor immediately stops even if
restarted.
: Check IPDU.
2. Phase-missing operation of power supply
• Check power voltage of R, S, T.
Coming-off, disconnection or short of
outdoor temp sensor
All stop
Displayed when
error is detected
1. Check outdoor temp sensor (TE, TS).
2. Check CDB.
Coming-off, disconnection or short of
outdoor temp sensor
All stop
Displayed when
error is detected
1. Check outdoor temp sensor (TD).
2. Check CDB.
Compressor drive output error
• Tin thermistor temp, Tin error
(IPDU heat sink temp. is high.)
Communication error between IPDU
• Connector coming-off between
CDB and IPDU
All stop
Displayed when
error is detected
1. Abnormal overload operation of
refrigerating cycle
2. Loosening of screws and contact error of
IPDU and heat sink
3. Cooling error of heat sink
4. Check wiring of CDB and IPDU.
Compressor does not rotate.
(Over-current protective circuit works
when constant time passed after
activation of compressor.)
All stop
Displayed when
error is detected
1. Compressor error (Compressor lock, etc.)
: Replace compressor.
2. Wiring trouble of compressor (Phase
missing)
Discharge temp error
• Discharge temp over specified
value was detected.
All stop
Displayed when
error is detected
1. Check refrigerating cycle. (Gas leak)
2. Error of electron control valve
3. Check pipe sensor (TD).
Compressor breakdown
• Operation frequency lowered and
stops though operation had
started.
All stop
Displayed when
error is detected
1. Check power voltage. (AC200V ± 20V)
2. Overload operation of refrigerating cycle
3. Check current detection circuit at AC side.
High-voltage protection error by TE
sensor
• TE temp over specified value was
detected.
All stop
Displayed when
error is detected
1. Overload operation of refrigerating cycle
2. Check outdoor temp sensor (TE).
DC outdoor fan motor error
• IDC operation or lock was
detected by DC outdoor fan
driving.
All stop
Displayed when
error is detected
1. Position detection error
2. Over-current protection circuit operation of
outdoor fan drive unit
• Check CDB.
• Refer to Judgment of outdoor fan.
Error on IPDU position detection
circuit
All stop
Displayed when
error is detected
1. Position detection circuit operates even if
driving by removing 3P connector of
compressor.
• Replace IPDU.
Coming-off, disconnection or short of
outdoor temp. sensor
Operation
continues
Displayed when
error is detected
1. Check outdoor temp sensor (TO).
2. Check P.C. board.