I have a York 80 home heating system thats 6 years old. This year I've had a nonstop problem with the unit. When the thermostat calls for heat, the pressure switch goes on and the ignitor lights for about 8 - 15 seconds but the flames don't go on. Initially I was told that it was a flame sensor problem. So the tech replaced it and told me that all was fine. He told me that in the future, if this occurs again, just remove the flame sensor, clean off the metal prong with a soft steel wool and put it back. This was back in January. Every other day since January, I've had to remove the flame sensor, clean it and pur it back so that the unit's flames will go on. Could anyone give me their thoughts on this problem. Could this be a control board problem. The furnace is located on the second floor of a 3 story house on ceramic floors.