Only 4-Way Valve Does Not Operate (During Heating Operation) - Toshiba RAS-10YKH-E Service Manual

9-3-6. Only 4-Way Valve does not Operate (During Heating Operation)

Shut off the power supply
from AC outlet once and
turn it on after 5 seconds.
Does the OPERATION lamp blink?
YES
Does the power turn on by
pushing the [START/STOP] button
of the remote control?
YES
Is the voltage across the terminal
( 2 - 3 ) 220-240 V?
YES
Is cable connection between indoor
and outdoor units correct?
YES
Is the voltage across the terminal
( 2 - 3 ) 220-240 V?
YES
Is the wiring of solenoid coil
for 4-way valve normal?
YES
4-way valve is defective.
NO
See "Power can not be turned on".
NO
See "Power can not be turned on".
NO
Relays (RY02, RY04)
or IC31 or IC30 is failure.
NO
Correct cabling between indoor
and outdoor units.
NO
Cables between indoor and
outdoor units are defective.
NO
Solenoid coil is defective.
– 49 –
Replace the
P.C. board.