Cobi may display a "recovery tank full" error if the tank is indeed full or if there is a clog in the line or squeegee. Follow these steps to resolve the error.
1. Double-check that the recovery tank has been emptied.
2. Check to see if the squeegee openings are clogged or blocked. Clean any debris blocking the openings and clean the squeegee assembly.
3. Check to see if the vacuum hose is clogged. Flush the vacuum hose using water or a Cobi Cannon tool.
Check out this video demonstrating how to use the Cobi Cannon.