Was here for a boiler cleaning. Performed preferred customer boiler cleaning. Cycled the boiler the boiler would not fire up. Called Dan Fox. Dan sent out Jeremiah. Figured out that the flame sensor was touching to ground causing the boiler to see a flame. Readjusted the flame sensor. The boiler fired up. The boiler is running normally at this time. The customer is getting a free air conditioning cleaning. Office to call in the spring to schedule the air conditioning cleaning.