ATU Maintenance Entity Training Homeowners! Learn to become a maintenance entity for your own ATU system. Contractors! Become a maintenance entity for certain systems used in Florida.*Systems eligible for training are limited. The classes do not count for CEU credit. Homeowner Registration Contractor Registration May ATU Homeowner Class cancelled due to low attendance! Example of permit Example of Site Plan SYSTEMS NOT PARTICIPATING: AquaKlear (601-936-7711), CajunAire (225-665-2949), Norweco (419-668-4471), and Orenco (541-459-4449)