Mitsubishi Electric CITY MULTI PUHY-P108 Service Handbook page 269

[ IX Troubleshooting ]
(2) Grouping of units in a system with multiple outdoor units
Error Code
6607 No ACK abnormality
(Contin-
ued)
Error
Error dis-
source ad-
play
dress
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) - (4) for sys-
knowl- tem with one outdoor unit
edgement (2) Disconnection or short circuit of
(ACK) at IC the transmission line for the out-
transmis- door unit on the terminal block
sion to RC 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.
Total capacity error (7100)
Capacity code error (7101)
Error in the number of con-
nected units (7102)
Address setting error (7105)
- 260 -
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)