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COMPRESSOR OIL FLUSHING PROCEDURE
To avoid problems when changing over to a new type
of oil (see table) a special Compressor Oil Flushing
Procedure has to be followed. The table is only valid
when the replaced oil has not exceeded its lifetime.
For more information consult Atlas Copco Service
dept.
Aged oil can be recognized best by using an oil
sampling analysis program. Indicators for aged oil are
strong smell, or contamination such as sludge and
varnish inside the oil vessel and oil stop valve or a
brownish colour of the oil.
Whenever aged oil is discovered, eg. when changing
the oil separator, contact Atlas Copco Service dept. to
have your compressor cleaned and flushed.
1. First thoroughly drain the system when the oil is 
warm, leaving as little oil in the system as 
possible, especially in dead areas, if possible blow 
out remaining oil by pressurising the oil system. 
Check the instruction manual for detailed 
description.
2. Remove the compressor oil filter(s).
3. Open the oil vessel and remove the oil separator 
element.
4. Check the interior of the oil vessel (see pictures). 
If  varnish deposits are discovered, contact Atlas 
Copco Service dept. and do not continue.
5. Put in a new oil separator, screw on new 
compressor oil filter(s) and close the oil vessel 
according to the instructions.
6. Fill the oil vessel with the minimum amount of 
replacement oil, run the compressor under light 
load conditions for 30 minutes.
7. Thoroughly drain the system when the oil is 
warm, leaving as little oil in the system as 
possible, especially in dead areas, if possible blow 
out remaining oil by pressurising the oil.
8. Fill the system with the final oil charge.
9. Run the compressor under light load conditions 
for 15 minutes and check for leakage. 
10.Check the oil level and top up if necessary.
11. Collect all waste lubricant used during the 
flushing process and dispose of it in accordance 
with the applicable procedures for managing 
waste lubricant.
Vessel cover 
contaminated clean
Vessel
contaminated clean
Not respecting compressor oil changing
intervals in accordance with the
maintenance schedule, can lead to
serious problems, including fire hazard!
The manufacturer does not accept any
liability for damage arising from not
following the maintenance schedule or
not using genuine parts.
Instructions on replacing the oil
separator element are available from
Atlas Copco Service dept.