Panasonic SCR-CH100H, Service Manual, Page: 14 / 22

11. COMPRESSOR TROUBLESHOOTING
DEFECTS
REASONS
When the winding insulation of the
compressor motor gets damaged
or punctured then the current flow
through the shell and gets
grounded.
When the winding insulation of the
compressor winding then due to
high temperature coil melt at any
point i.e. there is no continuous
path for the current to flow.
When the excess current flows
then high temp is generated in the
winding and there is chances which
may results in the damage or
failure of insulation of the winding.
RECTIFICATION
For any compressor defects first you
have to check the “continuity”
between the terminals and
compressor shell.
INSTRUMENT
1.Multimeter
2.Megger
3.Continuity
Tester.
1.Multimeter
2.Continuity
Tester.
Body Short.
Open winding.
Check the resistance and if the
reading is “Infinite” then replace the
compressor.
Short winding.
Check the resistance of winding, if
coil resistance is lesser than the
normal, then replace the
compressor.
1.Keep the supply at the lowest
voltage as per specifications with the
help of variac. If compressor does
not run then reject the compressor.
2.Keep the supply at the highest
voltage as per specifications with the
help of variac. If compressor does
not run then reject the compressor.
Check the discharge pressure at
compressor discharge end. If it is
less then 12.6kg/sq.cm compressor
is rejected as poor pumping.
Check the discharge pressure at
compressor discharge end. If it is
zero or negative then compressor is
rejected for no pumping.
If the compressor run for 30
seconds then starting current
exceeds 7 to 8 amps for 5 to 15
seconds and OLP trips off then the
compressor is rejected as Jammed /
High Amps.
Run the compressor for ½ hours
and check the quantity of oil at
discharge connector. If it is more
than 50cc.Then reject the
compressor for oil pumping.
Run the compressor and check the
abnormal noise. If it is, then replace
the compressor.
1.Multimeter.
No operation
at low voltage
or high
voltage. If the compressor does not operate
at low voltage or high voltage of the
compressor voltage range, the
compressor is rejected.
1.Multimeter.
Poor
pumping.
It is observed when there is brazing
leak inside the compressor at
discharge line-discharge connector
joint.
It is observed due to brazing failure
at discharge line-discharge
connector joints.
If there is jam in-between piston &
cylinder or any moving part of the
compressor. Then the starting
torque required will be more and
the compressor draws high
current .
Lubricant oil is filled in the
compressor for the cooling of
windings, moving parts. Some
times the compressor pumps out
oil along with the refrigerant.
Noise may be due to suction
muffler fitment loose, stator resting
spring loose, rotor shaft hitting to
the shell or foreign particle.
Dial pressure
gauge unit.
No pumping.
Dial pressure
gauge unit.
Jammed
(High A mps).
Ammeter.
Oil Pumping.
50.cc
measuring cup.
Noise. Test jig.
13