Bitzer Screw Compressor CSH/CSN Error Code AL5

Bitzer Refrigeration Major Pressure

Model: Screw Compressor CSH/CSN | Code: AL5

Applicable Systems
Octagon 4-Comp

Symptoms

The compressor reports high discharge pressure. The discharge pressure has exceeded the maximum safe operating limit.

Possible Causes

  • Condenser fouling or insufficient cooling capacity
  • Non-condensable gases trapped in the system
  • Refrigerant overcharge raising head pressure

Troubleshooting Steps

  1. Step 1: Clean condenser coils and verify all fans or water pumps operate
    Condenser operates at full cooling capacity
  2. Step 2: Purge non-condensables using a refrigerant recovery unit
    No non-condensables detected in the system
  3. Step 3: Check refrigerant charge by measuring subcooling
    Charge quantity matches the design value

How to Reset

To reset: Lower discharge pressure below the threshold, then reset the high-pressure safety.

Source: Bitzer Screw Compressor Operating Instructions, Bitzer Kuhlmaschinenbau GmbH

Category: Refrigeration