Mitsubishi Electric City Multi PQHY-P72 Service Handbook page 215

[ IX Troubleshooting ]
(2) Grouping of units in a system with multiple heat source units
Error Code
6607 No ACK abnormality
(Contin-
ued)
Error
Error dis-
source ad-
play
dress
LOSSNAY M-NET re-
(LC) mote con-
troller (RC)
MA remote
controller
(MA)
M-NET re- M-NET re-
mote con- mote con-
troller (RC) troller (RC)
MA remote
controller
(MA)
Error definition and error detection method
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).
Detection
Cause
method
No ac- (1) Same causes as (1) - (5) for system
with one heat source unit
knowl-
(Interlocked operation between LOSS-
edgement
NAY and the indoor units in the system
(ACK) at IC
in which the indoor units connected to
transmis-
different heat source units are
sion to LC
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 normal-
ly once, the following causes may be consid-
ered.
Total capacity error (7100)
Capacity code error (7101)
Error in the number of connected
units (7102)
Address setting error (7105)
No ac-
(1) Same causes as (1) - (4) for system
with one heat source unit
knowl-
(2) Disconnection or short circuit of the
edgement
transmission line for the heat source
(ACK) at IC
unit on the terminal block for central-
transmis-
ized control line connection (TB7)
sion to RC
(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.
Total capacity error (7100)
Capacity code error (7101)
Error in the number of con-
nected units (7102)
Address setting error (7105)
- 206 -
Check method and remedy
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)
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)