Service manual

33
●With the connector between the compressor and the intelligent
power module disconnected, activate the inverter and check if the
inverter is normal by measuring the balance of voltage between the
terminals.
<< Operation method>>
Start cooling or heating operation by pressing EMERGENCY OPERATION
switch on the indoor unit. (Test run operation : refer to 8-3.)
<<Measurement point>>
at 3 points
BLK (U)-WHT (V)
BLK (U)-RED (W)
WHT(V)-RED (W)
NOTE 1. Output voltage varies according to power supply voltage.
2. Measure the voltage by analog type tester.
3. During this check, LED of inverter P.C. board flashes 9 times.
●Measure the resistance between the terminals on the intelligent
power module.
<<Measurement point>>
at 6 points
BLK-WHT, WHT-BLK
BLK-RED, RED-BLK
WHT-RED, RED-WHT
<<Judgement>>
Infinite ["]···········Normal
0~dozens of ······Abnormal (short)
Output voltage 115V
w Measure AC voltage between
the lead wires at 3 points.
ohmmeter indication
Normal
(infinite)
Abnormal
(0~dozens of ")
X1
"
X1
"
LED
Inverter P.C. board
(Parts side)
9-time flash
2.5-second OFF
Flashing
Check of open phase
B
Check of intelligent power module
C
How to check inverter/ compressor
A
When POWER lamp flashes 5-time.
Outdoor unit does not operate.
Check the voltage
between terminals.
Check the
compressor.
Disconnect the connector (CN61)
between compressor and the
intelligent power module (IPM).
Check the resistance of the intelligent
power module.
See 11-6.D “Check of compressor” .
No
See 11-6.B “Check of open phase” .
See 11-6.C “Check of intelligent power module”.
Is the resistance
infinite?
Yes
Replace the inverter P.C.
board.
No
(0~several
")
Yes
Are the voltages
balanced?
Replace the inverter P.C.
board and compressor.
11-6. Troubleshooting flow
OB372D --2qxp 07.5.7 4:49 PM Page 33