Sounds like bigwheelingman was correct. My original HVAC mechanic did not know what he was doing(Not a small outfit). $750 later and still no heat, I had another HVAC company swing by my house because they were 2 streets down at another job. While using his meter he popped something in the furnace and jumped back. He determines my transformer is blown and says he has one on the truck. He comes back with an invoice for $200 for the transformer plus $89 service call. I told him to forget it. He also said I should cut my losses and spring for a new furnace. I went to a local HVAC supply, bought a $30 transformer and called an acquaintance knowledgable about electronics, that we had just met weeks earlier. Once the transformer was installed the control board was flashing the same code as my original(OLD) board was reading,(Limit open).He traced my problem to the High limit, which was loose and touching the sheet metal ultimately shorting the system. I watched him as he determined this to be the problem. The unit has been running perfect for 2-1/2weeks now. Ultimately this has been an $800 learning curve. I am only posting this as a warning to others. Do as mush research about the workings of your furnace as possible and stand with the tech(if you hire one) and ask questions. Call a local HVAC supply house and find out costs for the major parts. Research or use an HVAC company a friend or family member may recommend.