Well the tech checked things out and it looked like a sail switch problem so he replaced that and it worked good for about 2 days then started acting up again so he looked at the circuit board because he saw some corrosion on it from what looked like it got wet so he replaced that for just parts cost only and it seems to be working as it should but I am beginning to think it may very well be a limit switch because furnace burns well for about 6 to 8 minutes the burner shuts down but blower continues as it should clearing the gases but before blower shuts off the burner ignites and burns again for 6 to 8 minutes then repeats so it could be that limit switch shutting it down.