5-4. Air conditioner operates, but abnormalities are observed
5-4-1. Operation does not switch from HEAT to COOL (or COOL to HEAT)
Remote control unit
may be defective
Measure resistance of
4-way valve's winding (20S)
COOL to HEAT
Check voltage between terminals
N°4(+) N°6 at terminal plate
No voltage appears
Indoor PCB ass'y is defective
HEAT to COOL
Check voltage between terminals
N°4(+) N°6 at terminal plate
OK
(DC 24V)
(0V)
Receiver in lamp ass'y
may be defective
Outdoor PCB ass'y is defective
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