F8 error, ozone or auxiliary device not functioning correctly

Safety: Turn off power at the breaker before working on ozone or auxiliary circuits.

• Identify auxiliary device: Determine which accessory (ozone generator, UV sanitizer, etc.) is connected to the F8-related output on the Villeroy & Boch control pack.
• Disconnect accessory: Unplug the ozone generator or auxiliary device from the control pack and restore power. If F8 clears, the accessory is likely faulty.
• Inspect ozone tubing: Check the ozone injection line and check valve for kinks, blockages, or water intrusion into the ozone generator.
• Check for short circuits: Examine the accessory’s power cord and plug for damage or melted insulation.

If F8 remains even with the accessory disconnected, the auxiliary relay or control board output may be defective and should be evaluated by a technician.