A black Clean Filter Indicator could be the result of a clogged hose.
UPPER HOSE - Detach the hose from the machine. Insert a broomstick into the hose to push any obstruction through to the opposite end.
LOWER HOSE - Remove the screw from the left side of the lower hose on the back of the unit, and straighten this section of hose by pulling it down or lay the unit out flat, and roll the unit on its side with the lower house towards the top side. Look through the hose for any obstructions. Remove the hard plastic hose wand base (once held up by the single screw) to expose the lower hose. Push a broom stick through the lower hose to unclog. (The access plate can also be removed to provide a better view of the lower hose.) - Check the hose for any cracks or holes. Once the clog is cleared and the indicator remains black, double check to ensure the clog is eliminated and then turn the machine off and then back on. This should reset the indicator and resolve this issue.
If you continue to experience difficulty, please call Consumer Services at 1-800-263-2535, Monday - Friday 8 a.m. to 10 p.m., or Saturday 9 a.m. to 8 p.m., ET. A representative will assist you.