2205B0JE-DA-J-N_2014.05.
6 Troubleshooting
Screw Compressor J-series
6-10
Trouble
Direct causes
Factors
Actions
11
Abnormal
vibration
and/or
noise of
compressor
* Refer to Factor
“Insufficient
refrigerant
circulation
volume” in item
02 as well.
Rapid change from
unloaded operation
to full load
operation
Set control parameters so that rapid
change will not occur.
Or, re-adjust opening of oil
controller valve on capacity control
increase side towards the decrease
side.
Expansion valve
opening control
cannot keep up with
rapid changes in
heat load on load
side.
Avoid rapid changes in heat load
that exceed set response ranges of
the heat exchanger (evaporator) on
load side and expansion valve.
For details, refer to the instruction
manual related to devices/control
on load side.
Heat exchange
failure (insufficient
exchange) of heat
exchanger on load
side: defrost-related
For frosting (icing), defrost
manually.
Reduce defrost interval setting.
For malfunction of devices specific
to defrosting methods, remove the
cause and replace them.
For blocked piping routing specific
to defrosting methods, remove the
cause and take measures.
Especially for hot gas defrost type,
fully understand the unit operation
manual related to devices/control
on load side.
Liquid backflow
during operation
Heat exchange
failure (insufficient
exchange) of heat
exchanger on load
side: load side
conditions
Improve the environment if heat
exchanger is excessively loaded
and impacts ventilation.
* Make sure that the flow of heating
medium for heat exchanger on
load side is stable.
Heat exchange
failure (insufficient
exchange) of heat
exchanger on load
side: heat
exchanger
conditions
Inspect for blockade around heat
transmission tube and
malfunctioning fans. If any, take
measures.
Foreign substances
contaminating
compressor
Contamination of
welding spatter,
etc., from upstream
side
Inspect suction strainer and oil filter.
If any problems to element, replace
it.
Overhaul compressor.
Collect foreign substances and
objects. Identify the source and take
measures.
Neglect of
collecting tools and
rags during
overhaul