Mitsubishi Electric MXZ-8B140VA Technical & Service Manual page 43

8-8. FUNCTION OF SWITCHES, CONNECTORS AND JUMPERS
(1) Function of switches
Type of
No.
Switch
Switch
1
2
Abnormal history clear
3
4
Dip
SW1
switch
5
6
1
SW4
2
Forced defrost should be done as follows.
1 Change the DIP SW1-1 on the outdoor controller board from OFF to ON.
2 Forced defrost will start by the above operation 1 if these conditions written below are satisfied.
• Heat mode setting
• 10 minutes have passed since compressor started operating or previous forced defrost finished.
• Pipe temperature is less than or equal to 8:.
3 Forced defrost will finish if certain conditions are satisfied.
wForced defrost can be done if above conditions are satisfied when DIP SW1-1 is changed from OFF to ON.
After DIP SW1-1 is changed from OFF to ON, there is no problem if DIP SW1-1 is left ON or changed to OFF again. This
depends on the service conditions.
OCH480A
Function
Forced defrost
No function
ON
ON
ON
<Example>
Self-diagnosis
(Indoor unit selection)
A
RC
Indoor
No.1
BC#1 : branch box controller unit Number 1
BC#2 : branch box controller unit Number 2
Test run
Test run mode setting
The black square (■) indicators a switch position.
Action by the switch operation
ON
Start
Clear
—
ON
1 2 3 4 5 6 1 2 3 4 5 6
Indoor No.1 Indoor No.2
ON
1 2 3 4 5 6 1 2 3 4 5 6
Indoor No.4 Indoor No.5
ON
1 2 3 4 5 6 1 2 3 4 5 6
Indoor No.7 Indoor No.8
OC
BC#1 (5- branch type)
B C D E
IC IC IC
R
RC
C
Indoor Indoor
No.2 No.3
1 blinking LED2 (branch box controller board)
2 blinking LED2 (branch box controller board)
Operating
Heating
43
Effective timing
OFF
When compressor is
Normal operating in heating
operation.
Normal
off or operating
—
ON
1 2 3 4 5 6
Indoor No.3
ON
1 2 3 4 5 6
Indoor No.6
Indicating a particular
self-diagnosis
BC#2 (3- branch type)
A B C
IC IC
R R
C C
Indoor Indoor
No.4 No.5
OFF
Under suspension
Cooling
—