Mitsubishi Electric PUHY-P168, Service Handbook

Page: 267 / 404

- 258 -
[
IX
Troubleshooting ]
(1) System with one outdoor unit
Error Code Error definition and error detection method
6607 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
Outdoor
unit (OC) M-NET re-
mote con-
troller (RC)
MA remote
controller
(MA) No ac-
knowl-
edgement
(ACK) at
IC trans-
mission to
OC (1) Contact failure of transmission
line of OC or IC
(2) Decrease of transmission line
voltage/signal by exceeding ac-
ceptable range of transmission
wiring .
Farthest:
200 m [656ft] or less
Remote controller wiring:
10m [656ft] or less
(3) Erroneous sizing of transmission
line (Not within the range below).
Wire diameter:
1.25mm
2
[AWG16] or more
(4) Indoor unit main board failure
Turn off the power source of the outdoor
unit, and turn it on again.
If the error is accidental, it will run normally.
If not, check the causes (1) - (4).
Indoor
unit
(IC) M-NET re-
mote con-
troller (RC)
MA remote
controller
(MA) No ac-
knowl-
edgement
(ACK) at
RC trans-
mission to
IC (1) When IC unit address is
changed or modified during op-
eration.
(2) Faulty or disconnected IC trans-
mission wiring
(3) Disconnected IC connector
(CN2M)
(4) Indoor unit board failure
(5) M-NET remote controller failure
Turn off the outdoor/indoor units for 5 or
more minutes, and turn them on again.
If the error is accidental, they will run nor-
mally.
If not, check the causes (1) - (5).
LOSSNAY
(LC) M-NET re-
mote con-
troller (RC)
MA remote
controller
(MA) No ac-
knowl-
edgement
(ACK) at IC
transmis-
sion to LC (1) The power source of LOSSNAY
has been shut off.
(2) When the address of LOSSNAY
is changed in the middle of the
operation
(3) Faulty or disconnected transmis-
sion wiring of LOSSNAY
(4) Disconnected connector (CN1)
on LOSSNAY
(5) Controller failure of LOSSNAY
Turn off the power source of LOSSNAY and
turn it on again.
If the error is accidental, it will run normally.
If not, check the causes (1) - (5).
M-NET re-
mote con-
troller(RC) M-NET re-
mote con-
troller (RC)
MA remote
controller
(MA) No ac-
knowl-
edgement
(ACK) at IC
transmis-
sion to RC (1) Faulty transmission wiring at IC
unit side.
(2) Faulty wiring of the transmission
line for M-NET remote controller
(3) When the address of M-NET re-
mote controller is changed in the
middle of the operation
(4) M-NET remote controller failure
Turn off the power source of the outdoor
unit for 5 minutes or more, and turn it on
again.
If the error is accidental, it will run normally.
If not, check the causes (1) - (4).