At 2237, Station 85 was alerted for an AFA on Mariners Circle, in the Heritage Creek Development. Deputy Chief Clark responded in 85 Command and arrived seconds before Engine 4 to find nothing evident with the homeowner advising he had an odor in the home. Engine 4 arrived and took the 1st Due engine assignment and began investigation. Ladder 85 arrived next and took the 1st Due Special. Crews checked the entire home with no results. Deputy Chief Clark placed the scene under control and units cleared a short time later. Units responding, 85-8, Engine 4, Ladder 85, B-85, DSFP.