Mitsubishi Heavy Industries SRK25GZ-L1 Handbook page 46

SRK-GZ
(6) Inspection procedures of indoor electrical equipment
Is fuse (3.15A) blown?
YES
Is voltage applied between CNC
1~2 at transformer's secondary
side? (Approx. 12V)
YES
Is voltage applied between
terminals 1~2 on terminal
block? (220/240V)
YES
Is DC 0~12V detected between
terminals 2~3 on terminal
block?
YES
Indoor electrical equipment
are normal.
(7) Inspection procedures of inverter assembly
When the inverter is judged to be defective as a result of diagnosis of the item (2) above, inspect the inverter assembly as follows.)
(a) Diagnosis procedure (For further details, refer to the Inspection points of outdoor unit on the next page.)
Is visual check result OK?
1 YES
Is voltage applied to electrolytic
compressor? (Approx. DC 300V)
2
NO
Is electrolytic capacitor good?
YES
3
Is voltage applied between 3~4
of noise filter? (AC 220/240V)
YES
Defective PCB
(Including power
transistor)
44
NO
Replace fuse.
Notes (1) Since the communication timing signal is transmitted only when the
NO
Check power supply,
replace transformer.
NO
Replace PCB.
NO
Replace PCB.
YES
Defective PCB
NO
Defective electrolytic capacitor
NO
Defective noise filter
52C is turned ON, check it under the operating condition.
(2) Check the voltage on the terminal block.
¡ Power supply: Between 1~2 (AC 220/240V)
¡ Signal: Between 2~3 (Changing between DC 0~Approx. 12V)
Checks 1 and 3 must be made under the operating
condition.
Before checking 2, make sure to turn power off, dis-
charge electricity from the capacitor and check the re-
sidual voltage (10V or less) with a tester for safety.
Soldering iron