Mitsubishi Electric PUHZ-P100VHA.UK Service Manual page 29

Error Code Meaning of error code and detection method
Indoor/outdoor unit connector
mis-wiring, excessive number of units
(4 units or more)
1. Outdoor controller circuit board can
automatically check the number of
connected indoor units. Abnormal if the
number cannot be checked automatically
due to mis-wiring of indoor/outdoor unit
connecting wire and etc. after power is
turned on for 4 minutes.
EA
2. Abnormal if outdoor controller circuit
(6844)
board recognizes the number of
connected indoor units as "4 units or
more".
Mis-wiring of indoor/outdoor unit
connecting wire (converse 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 four minutes after power
on because of mis-wiring (converse wiring
Eb
or disconnection) of indoor/outdoor unit
(6845)
connecting wire.
Start-up time over
The unit can not finish start-up process
within four minutes after power on.
EC
(6846)
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 4 or more indoor units are
connected to one outdoor unit.
4 Defective transmitting receiving
circuit of outdoor controller
circuit board
5 Defective transmitting receiving
circuit of indoor controller
board
6 Defective indoor power board
7 Two or more outdoor units
have refrigerant address "0" .
(In case of group control)
8 Noise has entered into power
supply or indoor / outdoor unit
connecting wire.
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 circuit
board.
5 Defective transmitting receiving
circuit of indoor controller board
6 Defective indoor power board.
7 Two or more outdoor units
have refrigerant address "0" .
(In case of group control)
8 Noise has entered into power
supply or indoor/outdoor unit
connecting wire.
1 Contact failure of indoor/
outdoor unit connecting wire
2 Diameter or length of indoor/
outdoor unit connecting wire is
out of specified capacity.
7 Two or more outdoor units
have refrigerant address "0" .
(In case of group control)
8 Noise has entered into power
supply or indoor/outdoor unit
connecting wire.
29
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.
Total wiring length: 80m
(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.
3 Check the number of indoor units that are
connected to one outdoor unit. (If EA is
detected)
4~6 Put 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.
7 Check if refrigerant addresses (SW1-3 to
SW1-6 on outdoor controller circuit board)
are overlapping in case of group control
system.
8 Check transmission path, and remove the
cause.
w The descriptions above, 1-8, are for EA, Eb
and EC.