1. Overview

This procedure describes how to manually perform Backflushing on the AFU Filter when automatic backflushing is not functioning properly.

⚠ WARNING

• Operating the BFP (Backflushing Pump) without seawater flow, or following the steps incorrectly, may damage the equipment.

• HANLA IMS is not responsible for any damage resulting from the use of this manual method.

• If the filter is determined to be clogged, remove the Filter Element and clean it using approximately 100 bar high-pressure water.

2. Manual Backflushing Procedure

Step 1: Valve Preparation

• Arrange valves to allow seawater flow from Sea Chest to Overboard.

• Ensure all valves on the BFP (Backflushing Pump) discharge line are open (important).

Step 2: Enter Maintenance Mode

1. On the HMI, press MODE SELECT.

2. Press MAINTENANCE.

3. In the MAINTENANCE MODE screen, press the ON button (top-left).
   

Step 3: Open MV102 to 70%

1. Go to the MAIN section and press OPEN.

2. Check the box next to MV102.

3. Hold the OPEN button until MV102 reaches 70%.
   

Step 4: Open MV101 to 60%

1. Check the box next to MV101.

2. Hold the OPEN button until MV101 reaches 60%.
   

Step 5: Start Ballast Pump

• After confirming MV102 is at 70% and MV101 at 60%,
  start Ballast Pump and operate it for approximately 15 minutes.

• Ensure seawater is discharged smoothly overboard.

Step 6: Open FV105 and Start GM201

1. In the AFU section, press OPEN.

2. Check the box next to FV105.

   • Visually confirm FV105 is physically open on-site.

3. Check the box next to GM201.

   • The Geared Motor on the AFU top should begin rotating.
     

Step 7: Start BFP201

• After about 2 minutes, check the box for BFP201 to start the Backflushing Pump.
  

• Confirm:

  • Check that seawater is being discharged

  • The discharge line after FV105 becomes cold

⚠ Caution:
Do NOT run BFP if seawater is not flowing—this may damage the equipment.

Step 8: Stop BFP201

• After about 15 minutes, uncheck BFP201 to stop the pump.
  

Step 9: Restore Original System State

• Reverse all steps and restore the system to its original operating state.

3. Summary of Key Actions