Service manual

8
MFZ-KA09NA MFZ-KA12NA MFZ-KA18NA
7
SERVICE FUNCTIONS
7-1. TIMER SHORT MODE
For service, set time can be shortened by short circuit of JPG and JPS on the electronic control P.C. board.
The time will be shortened as follows. (Refer to 9-7.)
Set time: 1-minute 1-second
Set time: 3-minutes 3-seconds (It takes 3 minutes for the compressor to start operation. However, the starting time is
shortened by short circuit-of JPG and JPS.)
7-2. 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, both the P.C. boards of remote controller
and the electronic control P.C. boards must be modified according to the number of the indoor unit.
How to modify the remote controller P.C. board
Remove batteries before modification.
The board has a print as shown below :
NOTE: For modification, take out the batter-
ies and push the OPERATE/STOP
(ON/OFF) button 2 or 3 times at
first.
After finish modification, put back
the batteries then press the RESET
button.
The P.C. board has the print “J1” and “J2”. Solder “J1” and “J2” according to the number of indoor unit as shown in Table 1.
After modification, press the RESET button.
How to modify the electronic control P.C. board
Turn OFF the power supply before modification. Cut off “JR05” and “JR06” on the electronic control P.C. board according
to the number of indoor unit as shown in Table 2. (Refer to 9-7.)
No. 1 unit
No. 2 unit
No. 3 unit
No. 4 unit
1 unit operation
No modification
–
–
–
2 units operation
Same as at left
Solder J1
–
–
3 units operation
Same as at left
Same as at left
Solder J2
–
4 units operation
Same as at left
Same as at left
Same as at left
Solder both J1 and J2
No. 1 unit
No. 2 unit
No. 3 unit
No. 4 unit
JR05
No modification
Cut off JR05
No modification
Cut off JR05
JR06
No modification
No modification
Cut off JR06
Cut off JR06
JR06
JR05
CN211
Fuse (F11)
IC101
T11
VARISTOR (NR11)
Indoor electronic
control P.C. Board
CN212
CN151
CN152
CN1X1
CN1Y1
C111
R111
Table 1
Table 2
Remote controller model: KM05G
J2
J1
NOTE: After modification, turn ON the power supply and with the remote controller headed towards the indoor unit, press the
OPERATE/STOP (ON/OFF) button. If 1 or 2 beeps is heard from the indoor unit, modification is completed correctly.