Hitachi FSG Series Service Manual page 38

1
TROUBLESHOOTING
30
Phenomenon
Ref. Cycle is Different from
Overcharged Refrigerant
Decrease of
Faulty PCB
Discharge Gas
Superheat
Faulty
Discharge
Thermistor
Cause
the Electrical System
Faulty Ex. Valve
Fault
Disconnected
Wires for Ex.
Valve Control
Fault
Incorrect
Gas Mounting
Incorrect
Connection
Check Item
Check ref. cycle and
electrical system.
Measure pressure. (Refer to
Figure in Test Run of TC.)
Refer to 1.3.6.
Replace PCB and check
operation.
Check connections.
Measure resistance.
Check mounting state.
Check connections.
Action
(Turn OFF main switch)
Repair wiring.
Correctly charge
refrigerant.
Replace ex. valve if faulty.
Replace PCB if faulty.
Repair wiring connection.
Replace thermistor if
faulty.
Correctly mount
thermistor.
Remove looseness,
replace connector or
repair connections