the repairman thought the igniter might be getting bad.some said it could be a after drip?what is after drip and how is it corrected??when i looked in the firebox are running about 3 minutes, i could see like a white smoke going up.is that normal?i also dont see that blue smoke coming out the chimney all the time on start up only a couple of times usually at first start up in morning after waking up ,i turn it from 72 to 74 to warm the house up and then the smoke comes out.