I have a newlu installed Trane xv90 with a VisionPro 8320. This was a floor model with a 2002 manufacture date. Installed yesterday and all was fine. This morning blower was running but no heat. Red LED blinking twice indicating a system lockout. I reset and started up again, the ignitor fires the burners and then the burner immediately shuts off. I checked both vents and all is clear. Any ideas?