Toshiba Super MMU-AP0091H Service Manual page 105

8-5-2.
Operation from remote controller is not accepted and a check code is dis-
played on 7-segment display of the interface P.C. board of the header unit.
7-segment
Remote
display of
controller status
center unit
No response L08
E19-00
E19-02
E20-01
8-5-3.
There is no display of a check code on 7-segment display on the interface
P.C. board of the header unit though there is indoor unit which does not
accept the operation from the remote controller.
7-segment
Remote
display of
controller status
center unit
No response None
No display on None
remote controller
(No line is output.)
8-5-4.
In check for No. of connected outdoor units and connected Indoor units
after address setup, diminished No. of connected units displayed.
(There are outdoor/indoor units which do not operate in a test operation.)
Status
Number of connected Miswiring of communication line between
outdoor units is short. outdoor units or unconnected cable (Fig. 4)
(Address setup operation has finished without
recognition of miswired follower unit.)
Number of connected Miswiring of communication line between
indoor units is short. indoor units or unconnected cable (Fig. 5)
(Address setup operation has finished without
recognition of miswired indoor unit.)
Number of outdoor Remote controller is not connected with cable.
units connected to Miscabling of remote controller
group is short in
group operation from
Remote controller communication circuit error
remote controller.
If 230V is incorrectly applied to the remote
controller terminal, the remote controller
communication circuit fails.
Cause
Line addresses and indoor addresses of all the connected indoor
units are unset.
There is no header unit of group control.
Indoor unit power is not turned on.
Indoor/outdoor communication line is not correctly
connected to the header unit. (Fig. 1)
(Indoor/outdoor cannot
communicate before address setup.)
There is none of outdoor terminal resistance, or there are two or
more resistances. (Before address setup)
When connecting indoor/outdoor communication line between
outdoor units under condition of connected communication line
between outdoor units (Fig. 2)
SW08 setup error
Address setup is performed with connecting indoor/outdoor
communication line between outdoor units. (Fig. 3)
Address setup is performed under condition of connecting between
multiple refrigerant lines. (Fig. 3)
Cause
Communication line is not connected between indoor and outdoor.
Line and indoor addresses are unset.
(Unit which does not response to remote controller)
The power of the header unit of the group is not turned on in indoor
group control.(Unit which does not response to remote controller)
Group address is set up to follower unit in the individual control.
(Unit which does not response to remote controller)
The power is not turned on.
(Unit which is not displayed on remote controller)
Remote controller is not connected with cable.
(Unit which is not displayed on remote controller)
Miscabling of remote controller
(Unit which is not displayed on remote controller)
Remote controller communication circuit error
(Unit which is not displayed on remote controller)
If 230V is incorrectly applied to the remote controller terminal, the
remote controller communication circuit fails.
Cause
Set up addresses.
Set up group address.
Turn on the power again.
(In order of indoor → outdoor)
ON
1 2
Correct cabling.
SW30
Check SW30 bit 2 of the header unit.
No connection between multiple refrigerant
lines: SW30 bit 2 0N
Connection between multiple refrigerant lines:
SW30 bit 2 of the connected header unit is
turned on only in one line.
Correct cabling.
Turn all SW08 to OFF side.
Correct cabling.
Correct cabling.
Modify cabling.
Set up address.
Turn on the power.
Set [0] to group address in case of individual
control.
Turn on the power.
Correct cabling.
Correct cabling.
Remove FASTON terminal connected to
remote controller terminals (A/B), and check
the voltage. If voltage is not applied, replace
P .C. board. (15 to 18V usually)
Countermeasures
After modification of wiring, set up address again and check No. of the
connected outdoor units.
After modification of wiring, set up address again and check No. of the
connected indoor units.
Using the main remote controller connected to a group, start a test operation,
specify the unit which does not operate (Unit unconnected to group), and
then check cabling.
Using the main remote controller connected to a group, start a test operation,
specify the unit which does not operate (Unit unconnected to group).
Remove Fasten receptacle connected to remote controller terminals (A/B),
and check the voltage. If voltage is not applied, replace P.C. board.
(15 to18V in normal time)
105
Countermeasures
Countermeasures