Hitachi RAS-(3-6)HVNC1(E) - Page 329

8 Troubleshooting
315
SMGB0087 rev.0 - 12/2013
8
4-way solenoid
valve coil
Separation
resistance
Separation
resistance
Switch relay: ON
(Cooling/Heating)
Switch relay: OFF
(Cooling/Heating)
4-way solenoid
valve coil
Reversing valve relay: ON
Reversing valve relay: ON
Time Chart
Heating operation
Cooling operation
or
Defrost operation
Heating operation
4-way solenoid valve
SW1 is turned ON
for a second
(Occurs twice)
Current is carried only
when turning the reversion
valve relay ON
4-way solenoid valve relay
Cooling/Heating switch relay