2015 Lennox 80 Plus upflow basement install gas furnace Upon arrival today the system was at the set temperature and heating mode with the blower running. Heating appears to cycle on and off normal and is running at 134° in the supply plenum Homeowners complaint of furnace fan motor never turning off appears to have been resolved by resetting the thermostat fan mode to auto instead of on. Suspect children in the house inadvertently change the setting. Run test Lenox healthy climate powered 700 series humidifier and set to 35%, resurface flame sensor, run test heat mode Replace 16x25x1 pleated air filter from truck stock