Start heating operation.
(R25254)
NO
YES
YES
Four way valve
coil resistance at
440 - 750 ?
NO
Turn off the power and turn it on
again.
Replace the outdoor unit
PCB.
Replace the outdoor unit
PCB.
Replace the four way valve
coil.
Replace the four way valve.
NO
YES
S80 voltage at
0 VDC with compressor on?
S80
voltage at 120 -
380 VDC for 3 sec. after
compressor starts, and then at
about 10 - 24 VDC?
(Fig. 1)
Disconnect the four way valve coil
from the connector and check the
continuity.
(Fig. 1)
Voltage at S80
120 - 380 VDC
10 - 24 VDC
Time
Compressor
ON
3 sec.
< Caution on resetting the power supply >
Be sure to wait for 30 sec. or more after turning off the power.
Four way valve coil
Cooling / Dry : No continuity
Heating : Continuity