Display shows E15; heater may not detect flow correctly or may cycle on and off.

Safety: Turn off power and close water supply before opening hydraulic components.

• 1. Bleed air: Open a hot tap fully and allow water to run until all air is purged from the system. Some models have a dedicated bleed screw—follow Kospel instructions.
• 2. Clean hydraulic block: Remove the cover and access the hydraulic block. If possible, remove the flow meter/turbine and clean it with descaling solution to remove limescale and debris.
• 3. Check Hall sensor: Inspect the small electronic sensor attached to the flow meter. Ensure it is firmly mounted and its connector is secure on the PCB.
• 4. Replace components: If the turbine is worn or the Hall sensor tests faulty, replace the flow meter or entire hydraulic block assembly as recommended by Kospel.