![background image](http://html.mh-extra.com/html/daikin/ftxz25nv1b/ftxz25nv1b_service-manual_2459562162.webp)
Troubleshooting
SiMT041311E
147
Service Diagnosis
2.19 Input Overcurrent Detection
Error Code
E8
Method of Error
Detection
An input overcurrent is detected by checking the input current value with the compressor
running.
Error Decision
Conditions
The current exceeds 21 A for 2.5 seconds with the compressor running.
(The upper limit of the current decreases when the outdoor temperature exceeds a certain
level.)
Supposed
Causes
Outdoor temperature is out of operation range.
Defective compressor
Defective power module
Defective outdoor unit PCB
Short circuit
Troubleshooting
Check No.15
Refer to P.185
Check No.17
Refer to P.188
Check No.18
Refer to P.188
Caution
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
∗
An input overcurrent may result from wrong internal wiring. If the system is interrupted by an input
overcurrent after the wires have been disconnected and reconnected for part replacement, check the
wiring again.
(R20441)
NO
YES
YES
NO
Start operation and measure the
input current.
Check No. 18
Check the discharge pressure.
Check No. 17
Check No.15
Check with the inverter analyser.
Turn off the power and disconnect
the harnesses U, V, and W.
Turn off the power and reconnect
the harnesses. Turn on the power
again and start operation.
Check the installation condition.
Replace the outdoor unit
PCB.
Correct the power supply or
replace the outdoor unit
PCB.
Any LED off?
Input current flowing
above its stop level?
∗
Inverter analyser:
RSUK0917C
NO
Correct the power supply.
YES
Is the
power supply voltage
fluctuation within ±10% from
the rated value?