Performed heating maintenance 20x25x4 filter is good Pulled and cleaned flame sensor Condensate trap is clear High fire gas pressure 3.2" Temp rise 45 Low fire gas pressure 1.3" Temp rise 41 Blower is clean Burners are rust free Tested iwave Customer states they do not use the humidifier: left damper closed and water shut off to it. No concerns found on today's visit other than the water heater ready to start leaking on the cold water inlet. Sent over quote to replace the hot water tank