Furnace not heating burners will turn on but no heat locked out on code 2. Inspected the unit and found the burners where plugged up with rust and the flame sensor was dirty. Cleaned them both up and evething is operating properly at this time. Highly suggest getting the u it cleaned. It’s been 2 years and the system is 12 years old. Customer is getting a cleaning done on they furnace and the office will call to make they appointment. Thanks Brad If you could take a few minutes and fill out a quick survey on how I did today I would greatly appreciate it