mycom i160S - Page 104

2203M4JE-MY-iS2-N_2017.04.
Chapter 6 Troubleshooting
Screw Compressor i-series
6-6
Symptom
Direct cause
Root cause
Action
07
Leak from
mechanical
seal
Deteriorated part(s)
Swelled O-ring
* This occurs
when the
lubricating oil of
refrigerating
machine contains
large amount of
refrigerant.
In case of liquid flow-back,
remove the cause(s).
If oil heater or devices on its
control circuit are defective,
replace the defective part.
Deteriorated seal
ring/mating ring
If deteriorated over time, replace.
For other specific causes, see the
causes/action for symptom
"Overheating of sliding surface".
Incompatibility of
lubricating oil and
operating conditions
(such as working
temperature range
or refrigerant)
Unsuitable
lubricating oil was
selected, or
operating
conditions have
changed after
installation of the
package unit.
If possible, review the operating
conditions.
If not, see Section 4.1"Lubricating
Oil (Refrigerant Oil)" to select
suitable lubricating oil and replace
the whole quantity.
Poor contact of
sliding surfaces
Foreign matters
attached to sliding
surfaces, due to
contaminated
lubricating oil.
Replace the whole quantity of
lubricating oil.
Install bypass filter to oil supply
line.
Faulty assembly of
parts
Human error
Disassemble, replace parts and
reassemble.
Use assembly check sheet to
ensure confirmation.
08
Squeaking
sound from
mechanical
seal part
During initial period
after exchange for
new product,
squeaks may be
heard from sliding
surfaces until they
fit together.
As the sliding
surfaces are very
hard and dense,
they need time to
fit together.
Squeaking itself does not cause
leak from seal or deterioration in
sealing function.
Normally, squeaking is heard for
several dozens of hours, however,
it may last longer in rare cases.
→In this case, contact one of our
service centers.
09
Capacity
control
malfunction
Failure of capacity
control solenoid
valve, related
relays, or the like
Mostly caused by
coil burnout.
If deteriorated over time, replace.
If the symptom is caused by water
leakage, etc., remove the
cause(s) and then replace
defective part(s).
For details, refer to the instruction
manual of solenoid valve.
Internal leakage of
capacity control
solenoid valve
Aging degradation
Replace.
Capacity control oil
supply line is
defective.
Leak/clogging in
solenoid valve
gland or oil supply
piping
Remove cause, and check oil for
contamination, replace oil if
necessary.
10
Compressor
generates
abnormal
vibration
and/or
sound.
M rotor shaft runout
is excessive.
Lock nut(s) and/or
thrust bearing
gland(s) are
tightened unevenly.
If lock nuts are not loose and parts
such as thrust bearings are free of
defects, tighten the lock nuts
and/or thrust bearing glands
evenly.