Mitsubishi SRK18CL - Checking the indoor electrical equipment

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30
-
'12 • SRK-T-125
'09•SRK-SM-087D
(8) Checking the indoor electrical equipment
(a) Indoor PCB check procedure
Is there voltage between terminal
blocks
①
and
②
? (AC 220/230/240V)
Indoor electrical components
are normal.
Is there voltage between
terminal blocks ②and ③?
Inspect power source
for outdoor unit.
Replace fuse.
Replace indoor PCB.
Is the fuse burnt out? (3.15 A)
YES
YES
YES
NO
NO
NO
(b) Indoor unit fan motor check procedure
1) Indoor PCB output check
① ④ ⑤
2) Fan motor resistance check
⑥ ⑤ ④ ③ ② ①
⑥ ⑤ ④ ③ ② ①
FM I
DC15V
Indoor PCB
DC 308~336V
DC several V
(4~6 V)
CNU
(–)
GND
Blue Yellow White Black Red
Measuring point Resistance when normal
①

−

③
−
④ 
−
 ③
−
Measuring
point
Resistance when
normal
①

−

③
④

−

③
⑤ 
−
 ③
⑥

−

③
k
Force cooling operation
(AC 220/230/240V)