Troubleshooting The AquaClean filter symbol is flashing. Depending on how it is blinking (slow/fast), it tells you the filter is about to expire or you need to replace it. Read along the explanation. When it starts blinking slowly This is to alert you to buy/order a new Saeco AquaClean filter CA6903. When it starts blinking fast This indicates it is time to change the filter. Replace the Saeco AquaClean filter for a new one. Note: Always confirm the new filter in your espresso machine's menu. If the symbol stops blinking and disappears from the display The time to be able to change the Saeco AquaClean Calc and Water filter has passed. Before placing a new filter you now first need to descale your espresso machine.