Toshiba MMW-AP0481CHQ-E Service Manual page 95

Procedure 2: replacing P.C. board
1
Replace the trouble P.C. board with a service P.C. board.
Be sure to replicate the old jumper setting (removal) on the service P.C. board. (See the diagram at below.)
2
It is necessary to establish a one-to-one correspondence between the hot water module
being serviced and the remote controller.
Turn on the hot water module using one of the methods described below according to the system
configuration.
(1) Single (stand-alone) operation
Turn on the hot water module and proceed to Procedure 3.
(2) Group operation
A) If it is possible to selectively turn on the hot water module being serviced
Turn on the hot water module being serviced and proceed to Procedure 3.
B) If it is not possible to selectively turn on the hot water module being serviced (Case 1)
a) Temporarily disconnect the group control wiring from terminals A and B of the hot water module being
serviced.
b) Connect the remote controller wiring to the terminals, turn on the hot water module, and proceed to
Procedure 3.
* If this method cannot be used, proceed to the alternative method described below (Case 2).
C) If it is not possible to selectively turn on the hot water module being serviced (Case 2)
a) Remove the CN41 connectors of all other hot water modules in the same group.
b) Turn on the hot water module and proceed to Procedure 3.
Case 1
(*1)
Case 2
(*1)
Remove CN41
connectors of all
other indoor units
in same group.
* Be sure to restore the temporarily removed group control wiring and CN41 connectors to their initial states after
Procedure 3 has been completed.
(*1) Hot water module can connect up to 12 units in one refrigerative system.
SW501
J08
J01
J09
Hot water module Hot water module
Control P.C. board
Group control wiring
Hot water module Hot water module
Control P.C. board
Group control wiring
Hot water module (one being serviced)
Control P.C. board
Service Control P.C. board
Remote controller
Hot water module (one being serviced)
Control P.C. board
Service Control P.C. board
Remote controller
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Remove group control wiring from terminals
A and B of indoor unit being serviced, and
connect remote controller wiring.