F.387 — Burner in a fault state (Ground fault or BCU burner control unit faulty)

What does F.387 mean?

The burner is experiencing a fault, possibly due to a ground fault in the ionization circuit, an issue with the Burner Control Unit (BCU), or condensate backup.

• Ground fault, ionization current
• BCU burner control unit faulty
• Condensate backup

Click steps to track your progress.

1. 1

   Check if there is any condensate backup in the system; ensure the drain and siphon trap are clear.

2. 2

   Reset the appliance.

3. 3

   If the fault persists, contact a qualified technician to inspect the ionization electrode and connecting cable, or the BCU burner control unit.