I am a skilled professional that works for a Jerm's Plumbing, Heating & Air company. I recently completed an annual tune-up on a propane furnace. This involved cleaning the burners, heat exchanger, igniter, flame sensor, condensate trap, checking all safety controls, venting, fans, and overall furnace operation, bubble-testing the gas line, and checking carbon monoxide levels. I also verified that the system was operating properly at this time.