Hitachi RAS-(4-6)HVRNS2E - Page 224

8 Troubleshooting
214
SMGB0064 rev.0 - 08/2011
Phenomenon Cause Check item
Action
(Turn OFF the main switch)
Power failure or no power supply
Measure the voltage using the
tester
Supply the power
Blown out fuse for the power
source or activation of the outdoor
unit breaker
Short circuit between wires
Check the insulation material for
breaks
Remove the short circuit and
replace the fuse
Short-circuited wire to ground Measure the insulation resistance
Remove the short circuit to
ground and replace the fuse
Faulty comp. motor
Measure the resistance between
the wires and the insulation
resistance
Replace the comp. and the fuse
Faulty outdoor unit fan motor
Measure the resistance between
the wires and the insulation
resistance
Replace the outdoor unit fan
motor and the fuse
Blown out fuse for control circuit
or activation of outdoor unit
breaker
Short circuit between wires
Check the insulation material for
breaks
Remove the short circuit and
replace the fuse
Short circuit of the control circuit
(to ground)
Measure the insulation resistance
Remove the short circuit and
replace the fuse
Faulty solenoid coil for the
magnetic switch for the comp.
motor
Measure the resistance of coil
Replace the magnetic switch and
the fuse
Failure of the outdoor unit fan
motor
Measure the resistance between
the wires and the insulation
resistance
Replace the outdoor unit fan
motor and fuse
Faulty transformer Measure input voltage Replace transformer
Disconnected wires insufcient
contacting or incorrect connection
Between outdoor unit and indoor
unit
Check the continuity of the
wires. Check for looseness of the
connection screws. Check the
terminal nos.
Replacing wires repairing and
tightening the screws and the
correct wiring
Power source wiring for the outdoor
unit
Faulty PCB (outdoor unit, indoor
unit)
Disconnected wires to PCB Check the connections Correctly connect the wires
Faulty PCB — Replace PCB if faulty
Incorrect wiring
Disconnected wire; insufcient
contacting
Check the continuity and the
looseness of connection screws
Replacing wires, repairing and
tightening the screws
Incorrect wiring Check the terminal Nos. Correctly connect the wires
N O T E
• *1)
PCB1 output voltage Voltage
Vcc 12 – GND2 12 VDC
Vcc 05 – GND1 5 VDC
Vcc 15 – GND1 15 VDC
Vcc 24 – GND1 24 VDC
Vcc 12T– GND1 12 VDC