Sears hot air furnace

[LOCKr]

the unit fires,reaches it's startup temp (about 60 seconds), fan runs for about 30 seconds,as the fan starts it seems that the flame on the burner goes out and when the fan stops it's first cycle the ignitor re-lights the burner.Sometimes this happens twice but not always.Then the heat is on untill the stat temp is satified. Last night the unit did not come on at all.This morning I replaced the batteries in the stat(a Lux set for heat only)and it seems to operate okay but still has that recycling once before the burner stays on.Any suggestions? I've checked the forum for a simalar problem and there are a few but not exactly whats happening here. If I need to post any further info I can do that. Thanks for your time!

[Joel]

I presume you have a programable stat these tend to mess up esspeacialy on oil you may want to replace the stat ifyou want to check it you cross the two wires at the furnace which connect to the stat or you may feel more comfortable crossing them at the stst itself ,some furnaces after being shut down or off go through a cycle of operation which begins with the fan cycle