I got the following error code on my Carrier WeatherMaker 8000 two-Speed gas Furnace which was installed in 1995.
Abnormal Flame proving Signal. Flame is proved while gas valve is de-energized. Inducer will run until fault is cleared. Check for leaky gas valve or stuck-open valve.
I have had an odd phenomena going on since before Thanksgiving. Though 1) we have never smelled a ting of gas, and while 2) the thermostat setting is in the OFF position (No Heat NO cool) with 3) fan setting on auto (only two options - full-on or auto) and then this morning 4) I pulled face plate completly off of the thermostat, the exhaust fan just comes on when temps begin to drop and I get "Abnomal Flame" error code. You would think the heat sequence with burner ignition would follow but it doesn't. Instead the code goes back to normal and then if temps continue to drop the normal heating sequence (e.g., burner ignition) begins and the normal cycle (burner turnoff with heat distribution fan takes place. The house has never gone below or above the desired temp within more 1 to 2 degrees. The heating cycle operates perfectly.
Has anyone experienced this "exhaust fan with no burner ignition" phenomena? Since it appears the signal generating this phenomena is not coming from my thermostat which was disengaged this morning, where could it be coming from?