Bitzer Screw Compressor CSH/CSN Error Code AL20

Bitzer Refrigeration Minor Pressure

Model: Screw Compressor CSH/CSN | Code: AL20

Applicable Systems
Octagon 4-Comp

Symptoms

The compressor reports a discharge filter clogged alarm. The pressure drop across the discharge filter has exceeded the service threshold.

Possible Causes

  • Discharge filter element contaminated with oil or debris
  • Oil carry-over from separator clogging the filter
  • Filter at end of service life

Troubleshooting Steps

  1. Step 1: Measure pressure drop across the discharge filter
    Pressure drop exceeds the replacement threshold
  2. Step 2: Replace the discharge filter element
    New filter is installed with proper sealing
  3. Step 3: Check oil separator performance to prevent recurrence
    Separator is functioning correctly

How to Reset

To reset: Replace the discharge filter, then clear the alarm from the controller.

Source: Bitzer Screw Compressor Operating Instructions, Bitzer Kuhlmaschinenbau GmbH

Category: Refrigeration