Mitsubishi Electric PUHY-P168, Service Handbook, Page: 300 / 404

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[
IX
Troubleshooting ]
-
(2) Grouping of units in a system with multiple outdoor units
Error Code Error definition and error detection method
6607
(Contin-
ued)
No ACK abnormality The error is detected when no acknowledgement (ACK signal) is received after the
transmission. (eg. When the data is transmitted six times in a row with 30 seconds
interval, the error is detected on the transmission side.)
Note: The address/attribute appeared on the display on the remote controller
indicates the controller which did not provide the response (ACK).
Error
source ad-
dress
Error dis-
play
Detection
method
Cause Check method and remedy
LOSSNAY
(LC) M-NET re-
mote con-
troller (RC)
MA remote
controller
(MA) No ac-
knowl-
edgement
(ACK) at IC
transmis-
sion to FU (1) Same causes as (1) - (4) for sys-
tem with one outdoor unit
(Interlocked operation between
the transmission line and LOSS-
NAY in the system in which the
indoor units connected to differ-
ent outdoor units are grouped)
(2) Disconnection or short circuit of
the transmission line for the out-
door unit on the terminal block
for centralized control line con-
nection (TB7)
(3) When multiple outdoor units are
connected and the power source
of one of the outdoor units has
been shut off.
(4) The male power supply connec-
tor of the outdoor unit is not con-
nected to the female power
supply switch connector (CN40).
(5) The male power supply connec-
tors on 2 or more outdoor units
are connected to the female
power supply switch connector
(CN40) for centralized control.
If an error occurs, after the unit runs
normally once, the following causes
may be considered.
ΠTotal capacity error (7100)
ΠCapacity code error (7101)
ΠError in the number of connected
units (7102)
ΠAddress setting error (7105)
1) Turn off the power source of LOSSNAY
for 5 or more minutes, and turn it on
again. If the error is accidental, it will run
normally.If not, check the cause 2).
2) Check the causes of (1) - (5). If the
cause is found, correct it. If no cause is
found, check 3).
3) Same cause as that for indoor unit de-
scribed in 3)
M-NET re-
mote con-
troller (RC) M-NET re-
mote con-
troller (RC) No ac-
knowl-
edgement
(ACK) at IC
transmis-
sion to RC (1) Same causes as (1) - (5) for system
with one outdoor unit
(2) Disconnection or short circuit of the
transmission line for the outdoor unit
on the terminal block for centralized
control line connection (TB7)
(3) When multiple outdoor units are con-
nected and the power source of one of
the outdoor units has been shut off.
(4) The male power supply connector of
the outdoor unit is not connected to the
female power supply switch connector
(CN40).
(5) The male power supply connectors on
2 or more outdoor units are connected
to the female power supply switch con-
nector (CN40) for centralized control.
If an error occurs, after the unit runs normal-
ly once, the following causes may be consid-
ered.
ΠTotal capacity error (7100)
ΠCapacity code error (7101)
ΠError in the number of connected
units (7102)
ΠAddress setting error (7105)
1) Turn off the power source of LOSSNAY
for 5 or more minutes, and turn it on
again. If the error is accidental, it will run
normally.If not, check the cause 2).
2) Check the causes of (1) - (5). If the
cause is found, correct it. If no cause is
found, check 3).
3) Same cause as that for indoor unit de-
scribed in 3)
If the operation does not return to nor-
mal, check the causes (1) through (5).