Display shows E12 and the unit indicates a leak or overflow condition

Safety first: Immediately disconnect power and close inlet and outlet valves. Avoid standing in water near electrical outlets.

• Locate leak: Remove the front or side panels to access the base tray. Use a flashlight to identify the source of water (inlet fittings, outlet fittings, brine line, tank seams).
• Check overflow: Inspect the brine tank. If overfilled, the brine refill valve or float may be stuck. Clean or replace the float/air check assembly.
• Tighten fittings: Carefully tighten any loose compression or threaded fittings on the BWT connection block. Do not overtighten plastic parts.
• Dry leak sensor: Once the leak is fixed, dry the base tray and leak sensor completely with towels and allow air drying.
• Test: Slowly reopen the inlet valve while watching for new leaks. Restore power and confirm that E12 clears.

If leaks persist or a tank is cracked, stop using the unit and arrange for professional repair or replacement.