On 14 Dec 2005 20:26:39 -0800, wrote:

Thanks everyone.

It turns out that a camstat switch sensor is broken. The switch is not
reset-able. The switch has maximum temperature setting 210. Replaced
with a reset-able switch it is running fine now. Lennox furnace (G40)
may have a design flaw. It happens quite often.

Thanks again,
Shiling

You don't replace a non resetable limit switch with a resetable one.
That's done to alert you to a potential serious problem (IE. cracked
heat exchanger). If design was easy, we'd all be engineers.
Bubba