Mitsubishi FDU140VNXWVH - Page 171

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170
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'20 • PAC-SM-351
E59
1. Applicable model
5. Troubleshooting
All models
Diagnosis Countermeasure
Is DC15V
detected between ② and
③on CNI3?
Is the
pressure equalized
at starting OK?
Is the
insulation resistance
and resistance between terminals (1)
of compressor
OK?
In case that the compressor
does not start at all and no
sound or vibration exists
Is
power source voltage
OK?
NO
NO
NO
For
FDC100-140VNX-W
⑴
⑵
⑵
For
FDC100-140VSX-W
YES
YES
Is DC15V
detected after disconnecting
outdoor fan motor?
YES
Note(1) How to check voltage
at CN13 ⇒See E51
Note(2) Under anomalous
conditions, the voltage
becomes less than
DC14V
Replace outdoor unit control PCB.
Can compressor startup?
YES
NO
NO
NO
YES
YES
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(1) 1.044Ω or more at 20°C (Models FDC100-140VNX-W)
1.044Ω or more at 20°C (Models FDC100-140VSX-W)
Check the power source
voltage and correct it.
Replace inverter PCB.
If not solved yet, replace
noise lter PCB.
Replace outdoor fan motor.
OK
Check refrigerant amount
and refrigerant circuit.
Replace compressor.
2. Error detection method
When it fails to change over to
the operation for rotor position
detection of compressor motor
3 . Condition of error displayed
If the compressor fails to startup
for 20 times (10 patterns ×2
times) continuously.
4. Presumable cause
• Faulty outdoor fan motor
• Faulty outdoor unit control PCB
• Faulty inverter PCB
• Anomalous power source
voltage
• Insufficient or excessive
refrigerant amount
• Faulty component for
refrigerant circuit
• Compressor anomaly
(Motor or bearing)
Note: Insulation resistance
• The unit is left for long period without power source or soon after installation, insulation resistance may decrease to several MΩ or lower due to the liquid refrigerant
migrated in the refrigerant oil in compressor. If the electric leakage breaker is activated due to low insulation resistance, check followings.
➀ Check whether the insulation resistance can recover or not, after 6 hours has passed since power ON.
(By energize the crankcase heater, liquid refrigerant migrated in the refrigerant oil in compressor can be evaporated)
➁ Check whether the electric leakage breaker conforms to high-harmonic specications
(As INVERTR PAC units has inverter, in order to prevent from improper operation, be sure to use the breaker of high-harmonic type)
Error code
Remote control:
Content
5-time flashKeeps flashing
Stays OFF
––
Indoor display
RUN light TIMER light
Green LED
Yellow LED
Red LED
Outdoor unit
control PCB
Outdoor unit
inverter PCB
Compressor startup failure (1/2)