What does Kaeser alarm 0022 A (oil separator clogged) mean?
Short answer: Oil separator cartridge clogged (shutdown). If your Kaeser Sigma Control 2 is showing 0022 A — Oil separator Δp ⇞, 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?
Differential pressure across the oil separator cartridge is too high — the cartridge is clogged. Kaeser's remedy is to replace the oil separator cartridge.
Which machines show this?
the wide range of current-generation Kaeser rotary screw compressors — ASD, BSD, CSD, DSD, ESD and related series — built since roughly 2011 with the Sigma Control 2, the industrial-PC controller with a text display and RFID access. It reports faults as a four-digit number plus a letter: 'A' messages are alarms that shut the machine down, 'W' messages are warnings or service reminders it keeps running through, with arrows marking whether the value went over or under its limit — so 0015 A is the airend-overheat shutdown while 0013 W just asks for an air filter. Practical tip: the same subsystem often has a W and an A code (0004 W before 0022 A on the separator); acting on the W message is how you avoid the A shutdown.
What causes it?
- Oil separator cartridge clogged — replacement is the documented remedy
- Cartridge run past its service life, loading up with contaminants
Can you fix it yourself?
Only if trained — the diagnosis is done for you; the swap requires shutting down, isolating, and fully depressurizing the unit first.
Step by step — what to try, in order:
- Schedule an oil separator cartridge replacement as soon as possible.
- Only replace it yourself if you are trained on this machine — the unit must be shut down, isolated, and fully depressurized first.
When do you need a technician — and why?
The separator tank is a pressurized vessel; opening it without verified depressurization is genuinely dangerous, which is why untrained crews hand this to a service technician.
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 0022 A — Oil separator Δp ⇞ mean on a Kaeser Sigma Control 2?
Oil separator cartridge clogged (shutdown). Differential pressure across the oil separator cartridge is too high — the cartridge is clogged. Kaeser's remedy is to replace the oil separator cartridge.
Can I fix 0022 A — Oil separator Δp ⇞ on a Kaeser Sigma Control 2 myself?
Only if trained — the diagnosis is done for you; the swap requires shutting down, isolating, and fully depressurizing the unit first.
When does 0022 A — Oil separator Δp ⇞ on a Kaeser Sigma Control 2 need a technician?
The separator tank is a pressurized vessel; opening it without verified depressurization is genuinely dangerous, which is why untrained crews hand this to a service technician. Call a service technician to replace the cartridge if you are not trained to safely depressurize and open the oil separator tank.
Verified against service documentation: Kaeser Sigma Control 2 documentation for 0022 A — Oil separator Δp ⇞ (airsolcan.com)