E9 Drain Trouble - Mitsubishi Heavy Industries MHI FDU71VNXVF1 Technical Manual

Error code
E9
Remote control:
1. Applicable model
All models
2. Error detection method
Float switch is activated
3. Condition of Error displayed
If the float switch OPEN
is detected for 3 seconds
continuously or if float
switch connector or wire is
disconnected.
4. Presumable cause
• Defective indoor control PCB
• Float switch setting error
• Humidifier DM interlock
setting error
• Optional equipment setting
error
• Drain piping error
• Defective drain motor
• Disconnection of drain motor
wiring
Note:
When this error occurred at power ON, disconnection of wire or connector of the float switch is suspected. Check and
correct it (or replace it, if necessary).
LED Green Red
Keeps flashing 1 time flash
Indoor
Keeps flashing Stays OFF
Outdoor
5. Troubleshooting
Diagnosis
Check the error data in the remote control.
Is there any overflow?
YES
Is the humidifier connected?
YES
Is the
humidifier Drain Motor
interlocked by the indoor unit function
setting of remote
control?
YES
Drain motor ON from the remote control
Does DM operate?
YES
Is the drain
piping unclogged? Is the
drain pipe slop
OK?
155
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Content
Drain trouble
NO
Is DC12V
at CNI connector.
NO
YES
Is the
CNI connected
NO
firmly?
YES
Is
there any
NO
anomaly on the optional
equipment?
YES
NO
NO
Is
DC12V
NO detected at CNR
connector?
YES
NO
YES
-
'12 • PAC-T-178
Countermeasure
Check float switch.
Defective indoor control
PCB ➞ Replace.
Defective indoor control
PCB ➞ Replace.
Check optional equipment
Correct setting to
"Humidifier DM interlock".
Defective indoor control
NO
PCB ➞ Replace.
(Replace power PCB on
FDTC series.)
Check wiring of Drain
motor
Correct.
Check drain motor.