Furnace tune-up nd safety inspection. Cleaned and serviced the furnace. Tested all mechanical components. Cleaned all sensors. Cleaned out the condensation trap and all hoses. Cleaned all pressure switch hoses. Replaced the humidifier pad that the customer provided. Replaced the furnace filter that the customer provided. I noticed HSI was getting corroded. Replaced the hot surface ignitor. The system is clean, heating, and operating properly at this time. Customer renewed VIP maintenance plan.