Mitsubishi Electric PUZ-ZM200YKA2-ET Service Manual page 41

Check Code Abnormal points and detection method
Miswiring of indoor/outdoor unit
connecting wire
Outdoor controller circuit board can
automatically check the number of connected
indoor units. Abnormal if the number cannot
be checked automatically due to miswiring
of indoor/outdoor unit connecting wire, etc.
after power is turned on for 4 minutes.
Abnormal if outdoor controller circuit board
recognizes excessive number of indoor
units.
EA
(6844)
Miswiring of indoor/outdoor unit
connecting wire (reversed wiring or
disconnection)
Outdoor controller circuit board can
automatically set the unit number of indoor
units.
Abnormal if the indoor unit number can
not be set within 4 minutes after power
on because of miswiring (reversed wiring
Eb
or disconnection) of indoor/outdoor unit
(6845)
connecting wire.
Startup time over
The unit cannot finish Startup process within
4 minutes after power on.
EC
(6846)
OCH771C
Cause
Contact failure or miswiring of
indoor/outdoor unit connecting
wire
Diameter or length of indoor/out-
door unit connecting wire is out of
specified capacity.
Excessive number of indoor units
are connected to 1 outdoor unit.
(ZM60/71/100: 4 units or more
ZM125/140/200/250: 5 units or
more)
Defective transmitting receiving
circuit of outdoor controller circuit
board
Defective transmitting receiving
circuit of indoor controller board
Defective indoor power board
2 or more outdoor units have
refrigerant address "0" .
(In the case of group control)
Noise has entered into power
supply or indoor / outdoor unit
connecting wire.
Contact failure or miswiring of
indoor/outdoor unit connecting
wire
Diameter or length of indoor/out-
door unit connecting wire is out of
specified capacity.
Defective transmitting receiving
circuit of outdoor controller circuit
board
Defective transmitting receiving
circuit of indoor controller board
Defective indoor power board
2 or more outdoor units have
refrigerant address "0" .
(In the case of group control)
Noise has entered into power
supply or indoor/outdoor unit con-
necting wire.
Contact failure of indoor/outdoor
unit connecting wire
Diameter or length of Indoor/out-
door unit connecting wire is out of
specified capacity.
2 or more outdoor units have
refrigerant address "0" .
(In the case of group control)
Noise has entered into power
supply or indoor/outdoor unit con-
necting wire.
41
Judgment and action
Check disconnection or looseness or
polarity of indoor/outdoor unit connecting
wire of indoor and outdoor units.
Check diameter and length of indoor/out-
door unit connecting wire.
Total wiring length: 80 m
(including wiring connecting each indoor
unit and between indoor and outdoor unit)
Also check if the connection order of flat
cable is S1, S2, S3.
Check the number of indoor units that are
connected to one outdoor unit. (If EA is
detected)
– Turn the power off once, and on again
to check.
Replace outdoor controller circuit board,
indoor controller board or indoor power
board if abnormality occurs again.
Check if refrigerant addresses (SW1-3 to
SW1-6 on outdoor controller circuit board)
are overlapping in the case of group
control system.
Check transmission path, and remove the
cause.
Note:
The descriptions above, – , are for EA, Eb
and EC.