Hitachi RPI-0.8FSG1 Service Manual page 72

TROUBLESHOOTING
Alarm
Code
G "RUN" light flickers and "ALARM" is indicated on the remote control switch.
G The unit No., alarm code and the unit code is alternately indicated on the set temperature section,
and the unit No. and alarm code are indicated on the display of the outdoor unit PCB.
# This alarm code is indicated when a compression ratio, ε= {(Pd + 0.1) / (Ps + 0.1)} is calculated from
a discharge pressure (MPa) and suction pressure (MPa) and the condition lower than
ε = 1.8 occurs more than 3 times including 3 in one hour.
Does the inverter operate?
Does the compressor operate?
Is the four-way valve spindle
mounted at middle position?
Are the high-pressure sensor and
the low-pressure sensor good?
Is there a leak in the Solenoid
Valve for Hot Gas Bypass (SVA)?
Check if the intake air temperature is
too low at the indoor or outdoor units.
Phenomenon
Excessively
Low Compression
Ratio
1-62
Activation to Protect System from Low Compression Ratio
No
Yes
No
Yes
Yes
No
No
Yes
Yes
No
Cause
Inverter is not Functioning
Compressor is not Operating
Valve Stoppage at Medium
Position of 4-Way Valve
Abnormality of High or Low
Pressure Sensor
Excessively Low Indoor
Intake Air Temperature
Leakage from Solenoid
Valve: SVA Outdoor Unit
Leakage from Solenoid
Valve: SVD1, SVS1 of
CH Unit
<FX Series Only>
Check the inverter.
Check the compressor and
power cable.
Replace the four-way valve if faulty.
Replace the high-pressure sensor
or the low-pressure sensor if faulty.
Replace the Solenoid Valve
(SVA) if faulty.
Check Item
Check inverter.
Check compressor.
Measure suction pipe
temp. of 4-way valve.
Check connector for
PCB, power source and
pressure indication.
Check indoor unit and
outdoor unit air temp.
thermistor.
Check Solenoid Valve.
Check Solenoid Valve.
Action
(Turn OFF Main Switch)
Repair faulty part.
Replace comp. if faulty.
Replace 4-way valve
if faulty.
Replace sensor if faulty.
Replace thermistor
if faulty.
Replace SVA if leaking.
Replace SVD1 and
SVS1 if leaking.