American Standard 80 Furnace Manual American Standard Freedoom 80 Furnace Starts To Run, Then Stops?

American Standard Freedoom 80 furnace starts to run, then stops? - american standard 80 furnace manual

I have 2 years free 80th Oven never had a problem until today. He begins to run, for about 30 seconds can be. I hear the start and then turn off the burner. LED flashes constantly on-off rate in almost a blinking cursor on the computer, the manual says it's normal, "Cal for the heat." Any help would be very grateful. Cold to Woodstock!