Mitsubishi Electric City Multi CMB-P1016NU-G, Service Handbook

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[
IX
Troubleshooting ]
-
(2) Grouping of units in a system with multiple heat source 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 system
with one heat source unit
(Interlocked operation between the
transmission line and LOSSNAY in the
system in which the indoor units con-
nected to different heat source units
are grouped)
(2) Disconnection or short circuit of the
transmission line for the heat source
unit on the terminal block for central-
ized control line connection (TB7)
(3) When multiple heat source units are
connected and the power source of
one of the heat source units has been
shut off.
(4) The male power supply connector of
the heat source unit is not connected to
the female power supply switch con-
nector (CN40).
(5) The male power supply connectors on
2 or more heat source units are con-
nected to the female power supply
switch connector (CN40) for central-
ized 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 heat source unit
(2) Disconnection or short circuit of the
transmission line for the heat source
unit on the terminal block for central-
ized control line connection (TB7)
(3) When multiple heat source units are
connected and the power source of
one of the heat source units has been
shut off.
(4) The male power supply connector of
the heat source unit is not connected to
the female power supply switch con-
nector (CN40).
(5) The male power supply connectors on
2 or more heat source units are con-
nected to the female power supply
switch connector (CN40) for central-
ized 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 heat
source unit 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).