10
8-2. P.C. BOARD MODIFICATION FOR INDIVIDUAL OPERATION
A maximum of 4 indoor units with wireless remote controllers can be used in a room.
In this case, to operate each indoor unit individually by each remote controller, P.C. boards of remote controller must be
modified according to the number of the indoor unit.
8-1. TIMER SHORT MODE
For service, the following set time can be shortened by bridging the timer short mode point on the electronic control P.C.
board. (Refer to 10-7.)
Set time : 3-minute
→
3-second (It takes 3 minutes for the compressor to start operation. However, the starting time is
shortened by bridging the timer short mode point.)
NOTE
: While the relay 52C is ON, the compressor starting time cannot be shortened.
Table 1
1 unit operation
2 units operation
3 units operation
4 units operation
No. 1 unit
No modi
fi
cation
Same as at left
Same as at left
Same as at left
No. 2 unit
–
Cut J1
Same as at left
Same as at left
No. 3 unit
–
–
Solder J2
Same as at left
No. 4 unit
–
–
–
Cut J1 and solder J2
How to set the remote controller exclusively for particular indoor unit
After you turn the breaker ON, the first remote controller that sends the signal to the indoor unit will be regarded as the remote
controller for the indoor unit.
The indoor unit will only accept the signal from the remote controller that has been assigned to the indoor unit once they are
set.
The setting will be cancelled if the breaker is turned OFF, or the power supply is shut down.
Please conduct the above setting once again after the power has been restored.
How to modify the remote controller P.C. board
Remove batteries before modification.
The board has a print as shown below :
The P.C. board has the print “J1” and “J2”. Cut “J1” and “J2” according to the number of indoor unit as shown in Table 1.
After modification, press the RESET button.
NOTE :
For modification, take out
the batteries and press the
STOP/OPERATE/ (OFF/
ON) button 2 or 3 times at
first.
After finish modification,
put back the batteries then
press the RESET button.
MSZ-DM25VA MSZ-DM35VA
J2
J1
8
SERVICE FUNCTIONS
OBH750
