Only Case Of 151~251 Types; Only Case Of 301 Type - Mitsubishi Heavy Industries FDCA Series Technical Manual

S Only case of FDKN

Only case of 151~251 types

CNM
1 and 3 (Red – Black)
DC280V?
YES
CNM
4 and 3 (White-Black)
DC15V?
YES
Does the
fan motor turn
smoothly by
hand?
YES
Is the voltage
at CNM 5 (Yellow) DC 1V
or higher?
NO
Replacement indoor
unit control PCB

Only case of 301 type

CNM
1 and 4 (Red-Blue)
DC 0~60V ?
Turn the power off and wait
a short time (30 min. ~ 1 hr.)
YES
When tried again,
the fan goes ON.
YES
Replacement indoor
unit control PCB
3 (Black) is GND.
NO
Replacement indoor
unit control PCB
YES
3 (Black) is GND.
Secondary
NO
side of transformer
(red-red) 14V
or more
NO
Replacement transformer
NO
Detective fan motor
(2)
YES
Note (2) CNM 3 (Black) is GND.
3 (black) is GND.
YES
Replacement fan
NO
motor
YES
Check the
circumstances.
-
Abnormal data check
with remote controller
After check reset,
fan runs on Me.
NO
Fan ON?
YES
Was it reproduced?
YES
When the
motor is turning, does
NO
the voltage at CNM 6 (Blue)
fluctuate between
DC 0 ~ 15 V?
YES
Replacement indoor
unit control PCB
● Display conditions
If an indoor unit fan motor's speed is detected to be less than
200 rpm continuously for 30 seconds, the fan motor stops for 2
seconds. After 2 seconds, it starts again, but this occurs 4 times
within a period of 1 hour.
After check reset,
fan runs on Me.
NO
Fan ON ?
YES
Was it reproduced?
NO
YES
When
the motor is turning,
does the voltage at CNM 5
(White) fluctuate between
DC 0 ~ 15 V?
YES
Replacement indoor
unit control PCB
● Display conditions
If an indoor unit fan motor's speed is detected to be less than
200 rpm continuously for 30 seconds, the fan motor stops for 2
seconds. After 2 seconds, it starts again, but this occurs 4 times
within a period of 1 hour.
141
-
NO
Check the
circumstances.
(1)
Note (1) CNM 3 (Black) is GND.
NO
Check the
circumstances.
(1)
NO
Replacement fan
motor
Note (1) CNM 4 (Blue) is GND.