Analysis And Countermeasure Of Abnormalities - Hitachi SAMURAI Series Service Manual

4 Troubleshooting
Analysis and countermeasure of abnormalities

4.9 Analysis and countermeasure of abnormalities

Phenomenon
Power source
fuse blown
Control circuit
fuse blown
No operation
at all, even
if performing
operation
activation
Miswiring of remote control wiring
Open phase or reverse phase connection of
power source phases R, S, T
Defective remote control switch
Faulty PCB
Faulty
electromagnetic
switch of Pump
(52C)
Pump stops Activation of
before electromagnetic
compressor relay for pump
operation. (51P)
121 SMGB0120 rev.0 - 11/2017
Cause
Power failure
Power is not coming in
Short circuit between wires
Ground fault (Earth) of
wiring
Faulty compressor motor
Short circuit between wires
Ground fault (Earth) of
control circuit
Faulty electromagnetic
contactor coil of compressor
motor
Faulty electromagnetic
switch coil of pump motor
Faulty coil of the auxiliary
relay
Faulty solenoid valve coil
Faulty oil heater
Faulty transformer coil
PCB switch is set to "Local".
Bad connection of wiring
Faulty PCB
Disconnection of coil
Bad connection of contact
Pump locked
Inappropriate RC value of
overcurrent relay for Pump
Faulty overcurrent relay for
Pump
Check Item
Measure voltage with a
tester
Check main power switch
Check wire coating
damage
Measure insulation
resistance
Measure resistance
between wires and
insulation resistance
Check wire device damage
Measure insulation
resistance
Measure the coil
resistance
Replace solenoid valve and coil
Adherence of conductive
dirt
Measure secondary
voltage of transformer
Check wiring
Check connection of R, S,
T phases
Check the direction of the Replace remote control switch,
switch
Check connection with a
tester
Voltage measurement
between contacts of
electromagnetic switch
Check frozen water,
clogging by foreign bodies,
etc.
Check RC value and pump
operating current
Press reset button.
Check running current
Action · Countermeasure
Wait for power return
Turn main power switch ON
Replace fuse after correcting
short circuit
Replace fuse after correcting
ground fault
Replace compressor and fuse
Replace fuse after correcting
short circuit
Replace fuse after correcting
ground fault
Replace electromagnetic
contactor and fuse
Replace auxiliary relay and
fuse
Remove dirt and replace fuse
Replace transformer
Change wiring
Connect in-phase.
and set switch to "Remote".
Correct wiring connection
Replace PCB
Replace electromagnetic
switch of pump
Remove
Change RC value or replace
electromagnetic switch
Replace electromagnetic
switch
4