What does DP Oil Separ mean on an Atlas Copco compressor?
Short answer: Oil separator differential pressure high. If your Atlas Copco GA series (Elektronikon II regulator) is showing DP Oil Separ (oil separator pressure difference), the controller has logged a specific, documented condition. This page covers what it means, what causes it, what you can safely fix yourself, and when — and why — it takes a technician.
What exactly is the machine telling you?
The pressure drop across the oil separator element exceeded its programmed level (nominal 1 bar; recommended maximum 1 bar per Atlas Copco). A clogged separator wastes energy and raises running temperature, and triggers a service ('Inputs') message.
Which machines show this?
Atlas Copco GA-series oil-injected rotary screw compressors carrying the Elektronikon II regulator — the button-and-LCD controller generation that preceded the Mk 5 and Touch units, common on machines from the late 1990s and 2000s. Faults appear as plain-language messages such as *Shutd Warn* or *Serv Requir*, paired with the sensor name and the reading that caused them, and are cleared with the Rset key once the cause is gone. Warnings self-clear when the condition disappears; shutdowns latch until reset. Practical tip: the Status data menu tells you whether a service message came from a timer ('Plans') or a measured input like separator pressure drop ('Inputs') — check it before doing any work.
What causes it?
- Oil separator element clogged with age and contaminants — the normal wear-out
- Element left in service past its interval, wasting energy and raising running temperature
Can you fix it yourself?
The diagnosis is easy in-house — confirm the reading and order a genuine element. The swap itself is only DIY if your team is trained to depressurize the oil vessel.
Step by step — what to try, in order:
- Confirm the reading in the Measured data menu
- Schedule replacement of the oil separator element with a genuine Atlas Copco part
- After replacement, reset the service message via Status data > Inputs > Rset
When do you need a technician — and why?
The separator sits inside a pressurized oil vessel; opening it without full, verified depressurization is dangerous, which is why untrained teams should hand the swap to the distributor.
If it does come to a service call and you're in Nashville, TN or Birmingham, AL, we maintain independently compiled lists of local companies that service industrial air compressors — real businesses with verified contact information, none of whom paid to be listed.
Related questions
What does DP Oil Separ (oil separator pressure difference) mean on an Atlas Copco GA series (Elektronikon II regulator)?
Oil separator differential pressure high. The pressure drop across the oil separator element exceeded its programmed level (nominal 1 bar; recommended maximum 1 bar per Atlas Copco). A clogged separator wastes energy and raises running temperature, and triggers a service ('Inputs') message.
Can I fix DP Oil Separ (oil separator pressure difference) on an Atlas Copco GA series (Elektronikon II regulator) myself?
The diagnosis is easy in-house — confirm the reading and order a genuine element. The swap itself is only DIY if your team is trained to depressurize the oil vessel.
When does DP Oil Separ (oil separator pressure difference) on an Atlas Copco GA series (Elektronikon II regulator) need a technician?
The separator sits inside a pressurized oil vessel; opening it without full, verified depressurization is dangerous, which is why untrained teams should hand the swap to the distributor. Separator replacement requires depressurizing the oil vessel — if your team is not trained for that, have your Atlas Copco distributor do it.
Verified against service documentation: Atlas Copco GA series (Elektronikon II regulator) documentation for DP Oil Separ (oil separator pressure difference) (e-pneumatic.com)