Troubleshooting; 01: Compressor Does Not Start Up; 02: Compressor Stops Immediately After Startup - mycom 1612LSC series Instruction Manual

6

Troubleshooting

Table 6-1 describes typical trouble symptoms of compressors, their causes and actions to be taken.
The explanations of this Chapter are assumed that the compressor is used in the general refrigeration
cycle.

01: Compressor does not start up

Direct cause
Power source is off.
Main motor failure
"Micro-switch and
micro-switch cam" of the
indicator do not sense
capacity control of 0%.
Defective capacity control
oil supply line
Oil pressure not detected
Cooling water circulation
is not confirmed.
Failure of magnet, relay,
etc. in compressor startup
circuit

02: Compressor stops immediately after startup

Direct cause
Low pressure protection
circuit activates.
Compound 2-stage Screw Compressor 1612LSC Speed Increaser Type
Table 6-1 Troubleshooting
Root cause
Mostly caused by forgetting to
turn on after inspection.
Mostly caused by activation of
overload protection circuit.
Micro-switch failure
Loosening of micro-switch or
micro-switch cam set screw
due to vibration.
Improper adjustment of oil flow
control valve (throttled
excessively).
Leak/clogging in piping or
solenoid valve
Failure of oil pressure
protection device, pressure
sensor, relay, etc.
Pressure pipe is clogged.
Failure of devices such as
cooling water pump and
related circuits
Circulation route is clogged.
Aging degradation
Poor installation environment
Root cause
Insufficient refrigerant flow
 Insufficient refrigerant
6-1
2202L5JE-DA-C5-N_2015.05.
6 Troubleshooting
Action
Use a check sheet for post-inspection
actions and implement finger pointing
and call check to prevent forgetting.
Refer to the operation manual of the
motor for details including other
causes and actions.
Replace.
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".
Readjust.
Remove cause, and check oil for
contamination/replace oil.
Identify defective devices, investigate
causes of failure and take necessary
actions.
Then, replace failed device(s).
Remove clogging, and check oil for
contamination/replace oil.
Identify defective devices, investigate
causes of failure and take necessary
actions.
Then, replace failed device(s).
Remove the clogging.
Replace with new one.
Replace ventilation fans, etc. if
defective.
Improve temperature, humidity and
ventilation at the installation site.
Action
To correct insufficient refrigerant,
check leak, stop leak and then add
refrigerant.
* Also pay attention to moisture
entering into the system.