Mitsubishi Electric Mr.Slim PUH-P25VGAA Service Manual page 38

Error Code Meaning of error code and detection method
Indoor/outdoor unit connector mis-
wiring, excessive number of units (5
units or more)
1. Outdoor controller board can automati-
cally check the number of connected
indoor units. Abnormal if the number of
connected indoor units can not be set
within four minutes after power on
because of mis-wiring of indoor/outdoor
unit connecting wire and the like.
2. Abnormal if outdoor controller board rec-
EA
ognizes the number of connected indoor
(6844)
units as "5 units or more".
Mis-wiring of indoor/outdoor unit con-
necting wire (converse wiring or dis-
connection)
Outdoor controller board can automatically
set the unit number of indoor units.
Abnormal if the indoor unit number can not
be set within four minutes after power on
because of mis-wiring (converse wiring or
disconnection) of indoor/outdoor unit con-
necting wire.
Eb
(6845)
Start-up time over
The unit can not finish start-up process
within four minutes after power on.
EC
(6846)
Serial communication error
The communication between outdoor con-
troller board and M-NET p.c. board is not
available.
Ed
(0403)
Case
1 Contact failure or mis-wiring of
indoor/outdoor unit connecting
wire.
2 Diameter or length of
indoor/outdoor unit connecting
wire is out of specified capacity.
3 Five or more indoor units are
connected to one outdoor unit.
4 Defective transmitting receiv-
ing circuit of outdoor controller
board
5 Defective transmitting receiv-
ing circuit of indoor controller
board
6 Noise has entered into power
supply or indoor/outdoor unit
connecting wire.
7 Remote controller is wired up
among indoor units (twin, triple
or quadro units).
8 Two or more outdoor units has
refrigerant address "0."
(In case of group control).
1 Contact failure or mis-wiring of
indoor/outdoor unit connecting
wire
2 Diameter or length of
indoor/outdoor unit connecting
wire is out of specified capacity.
4 Defective transmitting receiving
circuit of outdoor controller board
5 Defective transmitting receiving
circuit of indoor controller board
6 Noise has entered into power
supply or indoor/outdoor unit
connecting wire.
7 Remote controller is wired up
among indoor units (twin, triple
or quadro units).
8 Two or more outdoor units has
refrigerant address "0."
(In case of group control).
9 Outdoor power supply board is
defective.
1 Contact failure of indoor/out-
door unit connecting wire
2 Diameter or length of indoor/
outdoor unit connecting wire is
out of specified capacity.
6 Noise has entered into power
supply or indoor/outdoor unit
connecting wire.
7 Remote controller is wired up
among indoor units (twin, triple
or quadro units).
8 Two or more outdoor units has
refrigerant address "0."
(In case of group control).
1 Breaking of wire or contact
failure of connector between
outdoor controller board and
M-NET p.c. board.
2 Contact failure of M-NET p.c.
board power supply line
3 Entrance of noise into trans-
mission wire
4 Defective transmitting receiv-
ing circuit of M-NET p.c. board
5 Defective serial transmitting
receiving circuit of outdoor
controller board
38
Judgment and action
1 Check disconnection or looseness or polarity
of indoor/outdoor unit connecting wire of
indoor and outdoor units.
2 Check diameter and length of indoor/outdoor
unit connecting wire.
Outdoor-indoor units' interval: 50m maximum
Indoor-indoor units' interval: 30m maximum
Also check if the connection order of flat
cable (VVF etc.) is S1, S2, S3.
3 Check the number of indoor units that are
connected to one outdoor unit. (If EA is
detected.)
45 Put the power off, and on again to check.
Replace outdoor controller board or indoor
controller board if abnormality is displayed
again.
Check the indoor/ outdoor unit connecting
wire.
6 Inspect transmission line to solve the problem.
7 Wire the remote controller to one of the mul-
tiple indoor units.
8 Set the refrigerant address of outdoor units
with different number starting from "0."
9 Unless the wire has contact failure, discon-
nect CN2S on indoor power supply board to
measure the voltage. When CN2S does not
have a current of DC12V to DC16V, replace
the indoor power supply board.
w The descriptions above, 1-9, are for EA, Eb
and EC.
1 Check disconnection, looseness, or breaking
of connecting wire between outdoor con-
troller board CN1 and M-NET p.c. board
CN5.
2 Check departure or looseness of M-NET p.c.
board power supply line (CND-TB1).
3 Replace M-NET p.c. board.
4 Replace outdoor controller board.