2205B0JE-DA-J-N_2014.05. 
6 Troubleshooting 
Screw Compressor J-series 
6-6 
  Trouble  Direct causes  Factors  Actions 
07 
 
Leak from 
mechanical 
seal 
Long stoppage 
period (no oil film 
on sliding surfaces)
 
Due to user’s 
specific conditions, 
such as heat load 
being intermittent. 
If stoppage period becomes more 
than one week, manually operate oil 
pump as well as turn rotor axis of 
compressor, or equip external seal 
portion with oil pot. 
Deteriorated parts 
 
Hardened O-ring  For aging degradation, replace 
O-ring. 
For other unique causes, the same 
factors and actions described in 
“Damaged sliding surfaces due to 
excessive heat of sliding surfaces” 
can be applied. 
Swelled O-ring 
* Occurs in 
excessive 
refrigerant 
dissolution oil 
For liquid backflow operation, 
remove the causes. 
For malfunction of oil heater and 
other devices on control circuit, 
replace them. 
Deteriorated seal 
ring or mating ring 
For aging degradation, replace 
parts. 
For other unique causes, the same 
factors and actions described in 
“Damaged sliding surfaces due to 
excessive heat of sliding surfaces” 
can be applied. 
Incompatibility 
between operating 
conditions (working 
temperature 
ranges, refrigerant, 
etc.) and lubricant 
Inappropriate lubri-
cant or change in 
operating 
conditions since 
installation of 
device 
Re-examine operating conditions if 
possible. 
If not, refer to Chapter 4.1, 
“Lubricant (Refrigerant Oil)”, and 
select lubricant again and replace 
all amount of current lubricant with 
new type. 
Bad contact 
condition of sliding 
surfaces 
Foreign matter 
attached to sliding 
surfaces due to 
contamination of 
lubricant 
Exchange all lubricant. 
Equip oil supply line with bypass 
filter. 
Faulty parts attach-
ment 
Human error 
Overhaul compressor to replace 
parts, and reassemble it. 
Check using assembly check sheet.
08 Squeaking 
sound from 
mechanical 
seal part 
During initial period 
after replacement 
until sliding 
surfaces fit 
together, squeaking 
sound caused by 
contact of sliding 
surfaces might be 
heard. 
Sliding surfaces are 
high in hardness as 
well as in density, 
so it takes a while 
for them to fit 
together. 
Squeaking itself does not cause 
leak from or functional deterioration 
of seal. 
Squeaking normally subsides after 
few dozens of hours, but it could 
continue in rare cases. 
→In this case, contact our service 
centers.