My
furnace burner wont shut down when the ambient temperature gets up to the selected number on the dial. I heated the copper tube (below the heater) that is the temperature sensor to 90 degrees fahrenheit and the burner still did not shut down. What would cause this to happen and how do I fix it.
I did clean and inspect the heater for rust out and cracks by removing it from the trailer and dismantling it. The burner would not
light to begin with as the orifice was plugged. Burner
lights fine and flame is good. The pilot has always worked fine.