mycom 3225**C Series User Manual

2202MYJE-MY-C8-N_2018.02.
Chapter 6 Troubleshooting
Compound 2-stage Screw Compressor 3225**C
6-8
10: Capacity control position is indicated incorrectly (continued)
Direct cause
Root cause
Action
Inaccurate reading of
capacity control indicator
on the control panel.
E/E positioner or/and indicator
is faulty.
If deteriorated over time, replace.
If there are specific causes such as
surge current, remove the cause or
take proper action.
Loosened terminals or
defective wires
Tighten the terminals if loosened.
Replace defective wires.
11: Capacity control malfunction
Direct cause
Root cause
Action
↑ See the causes for
"Inaccurate reading of
capacity control indicator
on the control panel".
Same as left
Same as left
"Micro-switches and
micro-switch cam" of the
indicator do not sense
"100%" position and/or
"0%" position.
Micro-switch failure
Replace.
Loosening of micro-switch or
micro-switch cam screw due to
vibration.
Adjust the position of the cam and
switch, and tighten them.
Use thread locking agent when
necessary.
When compressor's vibration is
unusually high, see Item No. 12
"Compressor generates abnormal
vibration and/or sound".
Failure of capacity control
solenoid valve or related
relays
Mostly caused by coil burnout.
If deteriorated over time, replace.
If the symptom is caused by wet with
water, 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
Oil compression due to
temperature rise inside
unloader cylinder
If the symptom is caused by long
duration of low-load operation, review
and improve the operating method.
Arrange inline check valve and oil
bypass route on the capacity control
oil supply line.
Defective capacity control
oil supply line
Improper adjustment of oil flow
control valve
Readjust.
Leak/clogging in solenoid valve
gland or oil supply piping
Remove cause, and check oil for
contamination/replace oil.
Unloader piston does not
move.
(Though this is one of the
causes of "Defective
capacity control oil supply
line", it is listed separately
here.)
Damage on the cap seal of the
piston
Check oil for contamination/replace
oil.
Replace O-ring, cap seal, etc.
Cap seal is pinched.
Replace O-ring, cap seal, etc.
Cap seal is worn.
Check oil for contamination/replace
oil. Replace O-ring, cap seal, etc.
There is residual refrigerant
gas inside unloader cylinder.
Stop the compressor. By operating the
oil pump, repeat load/unload
operation to purge refrigerant gas
from unloader cylinder.
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.

mycom 3225**C Series Specifications

General

Brand	mycom
Model	3225**C Series
Category	Compressor
Language	English