Mitsubishi Electric PUZ-HA24NHA1 Service Manual page 29

10-3. SELF-DIAGNOSIS ACTION TABLE
<Abnormalities detected when the power is turned on>
Check Code Abnormal point and detection method
None
OCH750A
1 No voltage is supplied to termi-
nal block(TB1) of outdoor unit.
a) Power supply breaker is
turned off.
b) Contact failure or disconnec-
tion of power supply terminal
c) Open phase (L1 or L2
phase)
2 Electric power is not charged
to power supply terminal of
outdoor power circuit board.
a) Contact failure of power
supply terminal
b) Open phase on the outdoor
power circuit board
Disconnection of connector
LI or NI
3 Electric power is not supplied
to outdoor controller circuit
board.
a) Disconnection of connector
(CNDC)
4 Disconnection of reactor (DCL)
5 Disconnection of outdoor noise
filter circuit board or parts fail-
ure in outdoor noise filter circuit
board. (HA42)
—
6 Defective outdoor power circuit
board
7 Defective outdoor noise filter
circuit board (HA42)
8 Defective outdoor controller
circuit board
Note: Refer to indoor unit section for the codes starting with P and E.
Cause
1 Check following items.
2 Check following items.
3 Check connection of the connector (CNDC)
4 Check connection of reactor. (DCL)
5 a) Check connection of outdoor noise filter
6 Replace outdoor power circuit board.
7 Replace outdoor noise filter circuit
8 Replace controller board (When items
29
Judgment and action
a) Power supply breaker
b) Connection of power supply terminal
block (TB1)
c) Connection of power supply terminal
block (TB1)
a) Connection of power supply terminal
block (TB1)
b) Connection of terminal on outdoor power
circuit board (HA24-36)
Connection of terminal on outdoor noise
filter circuit board (HA42)
Disconnection of connector LI or NI
Refer to "10-8. TEST POINT DIAGRAM".
on the outdoor controller circuit board.
Check connection of the connector, CNDC,
on the outdoor power circuit board. Refer to
"10-8. TEST POINT DIAGRAM".
Refer to "7. WIRING DIAGRAM".
circuit board.(HA42)
b) Replace outdoor noise filter circuit board.
Refer to "10-8. TEST POINT DIAGRAM".
(HA42)
board(HA42)
above are checked but the units cannot be
repaired).