Technician performed single system heating maintenance. Replaced 20 x 25 x 5 filter. Inspected electrical connections and components cleaned furnace, flame sensor, inspected heat, exchangers, rollout, switches, and general operation of heating. Quickly inspected outdoor unit and cleaned up system is operating normally at this time.. Please note that if you can avoid turning power off to the furnace, it is beneficial for the customer has had issues in the past with his echo, net wireless coming back online.