A no-heat service call was completed for a Lennox ML180 gas furnace in Salt Lake. I found the issue was a failed flame sensor, preventing the burner from igniting. I cleaned the flame sensor and tested the ignition, but the sensor was too worn. I replaced it with a new OEM part and checked the control board for any other issues. After completing the repair, I tested the furnace through a full heating cycle. The system is now operating efficiently, and heat was fully restored to the home, ensuring proper comfort for the winter season.