Mitsubishi Electric CITY MULTI PUHY-P108 Service Handbook page 301

[ IX Troubleshooting ]
(3) System connected to the system controllers (MELANS)
Error Code
6607 No ACK abnormality
(Contin-
ued)
Error
Error dis-
source ad-
play
dress
Outdoor M-NET re-
mote control-
unit
ler (RC)
(OC)
System con-
troller (SC)
MA remote
controller
(MA)
BC control-
M-NET re-
mote control-
ler (BC)
ler (RC)
system con-
troller (SC)
MA remote
controller
(MA)
Indoor M-NET re-
unit mote con-
(IC) troller (RC)
system
controller
(SC)
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- Same cause as that for system with
knowl- one outdoor unit
edgement
(ACK) at
BC trans-
mission to
OC
No ac- Same cause as that for system with
knowl- one outdoor unit
edgement
(ACK) at IC
transmis-
sion to BC
Same as grouping of units in a sys-
No acknowl-
edgement
tem with multiple outdoor units
(ACK) at RC
transmission
to IC
No ac- 1. Error occurrence on some IC
knowl- (1) Same cause as that for system
edgement with one outdoor unit
(ACK) at
2. Error occurrence on all IC in the
SC trans-
system with one outdoor unit
mission to
(1) Total capacity error (7100)
IC
(2) Capacity code error (7101)
(3) Error in the number of connected units
(7102)
(4) Address setting error (7105)
(5) Disconnection or short circuit of the
transmission line for the outdoor unit
on the terminal block for centralized
control line connection (TB7)
(6) Turn off the power source of the out-
door unit
(7) Malfunction of electrical system for the
outdoor unit
3. Error occurrence on all IC
(1) Same causes as (1) - (7) described in
2.
(2) The male power supply connectors on
2 or more outdoor units are connected
to the female power supply switch con-
nector (CN40) for the transmission line
for centralized control.
(3) Disconnection or shutdown of the pow-
er source of the power supply unit for
transmission line
(4) System controller (MELANS) malfunc-
tion
- 292 -
Check method and remedy
Same remedy as that for system with one
outdoor unit
Same remedy as that for system with one
outdoor unit
Same remedy as that for grouping of units in
a system with multiple outdoor units
Same remedy as that for system with
one outdoor unit
1) Check the LED display for troubleshoot-
ing on the outdoor unit.
->If an error is found, check the check
code definition, and correct the error.
->If no error is found, check 2).
2) Check (5) - (7) on the left.
Check voltage of the transmission line for
centralized control.
20V or more : Check (1) and (2) on the
left.
Less than 20V : Check (3) on the left.