Mitsubishi Electric AE-200A Service Handbook page 60

[V Troubleshooting]
Error Description and method
code of detection
Communication error -
No ACK return
Error detected by the
controller on the
transmission side
when there is no reply
(ACK signal) from the
other party after
transmission.
* If recovery from the
error is not possible with
this check method and
solution, refer to the
service manual of the
air-conditioning unit.
6607
Cause
Occurrence source address: Outdoor unit
1) The transmission line of the centralized
control terminal block (TB7) of the outdoor
unit is disconnected or shorted.
2) Power of the outdoor unit is shut off.
3) The electric system of the outdoor unit has
failed.
4) When the address of the outdoor unit
changes or is changed part way through
or when the error occurred after normal
operation was performed once, there are
the following causes.
・ System abnormality - Total capacity error (7100)
・ System abnormality - Capacity code error (7101)
・ System abnormality - Connecting unit number
excess (7102)
・ System abnormality - Address setting over 254
(7105)
Occurrence source address: Indoor unit
a) Error for only some indoor units.
1) When the address of the indoor unit
changes or is changed part way
through.
2) The transmission line of the indoor unit
is defective or disconnected.
3) The connector (CN2M) of the indoor
unit is disconnected.
4) The indoor unit controller has failed.
b) All indoor units in one refrigerant system
are in error
5) Outdoor unit detects the error.
・ System abnormality - Total capacity error (7100)
・ System abnormality - Capacity code error (7101)
・ System abnormality - Connecting unit number
excess (7102)
・ System abnormality - Address setting over 254
(7105)
6) The transmission line of the
centralized control terminal block
(TB7) of the outdoor unit is
disconnected or shorted.
7) Power of the outdoor unit is shut off.
8) The electric system of the outdoor unit
has failed.
9) The address switch of the outdoor unit
is mistakenly set to 000 (00).
c) All indoor units are in error
10) When a power supply unit for the
transmission line is used, the power
jumper (CN40) is inserted for
supplying power to the centralized
control transmission line of the
outdoor unit.
11) When outdoor units are used, the
power jumper (CN40) is inserted for
supplying power to the centralized
control transmission line of multiple
outdoor units.
12) The transmission line power supply
unit is disconnected or the power is
shut off.
13) The AE-200/AE-50/EW-50 has failed.
Occurrence source address: Remote controller
* Same as when the occurrence source is an indoor unit (Read that section and replace the term
"indoor unit" with "remote controller" or "system remote controller")
56
Check procedure and remedy
a) Check causes 1) to 4).
Fix the problem if you find the cause, and
proceed to b) if you do not find the cause.
b) Shut off the power of the
AE-200/AE-50/EW-50 and then turn it back
on.
Fix the problem if you find the cause, and
proceed to c) if you do not find the cause.
c) Check whether or not an error has occurred
by checking the remote controller or the LED
for failure diagnosis on the outdoor unit.
When there is an error
→ Fix the failed part in accordance with the
details on the error code.
Turn off the power of the outdoor units and indoor
units at the same time, leave it off for at least 5
minutes, and then turn it back on. Shut off the
power of the AE-200/AE-50/EW-50 and then turn
it back on.
The equipment recovers normally if an
unexpected error occurred. If it does not recover
normally, check causes 1) to 4).
a) Check the failure diagnosis LED on the
outdoor unit.
→ When an error is occurring, perform a
check in accordance with the details on
the error code.
→ When an error is not occurring, proceed to
b)
b) Check the details of causes 6) to 9).
Check the voltage of the centralized control
transmission line. (Voltage between A and B of
TB3 in the case of the AE-200/AE-50/EW-50)
・
When 17 V or higher
→ Check causes 5) to 11)
・
When less than 17 V
→ Check cause 12)
Occurrence source address: System remote controller