Hi. My Lennox furnace is about 8 years old and has worked fine the past few years. This year it started acting up. Well, at first we thought it was the thermostat, so we replaced it. We still had problems after that so we called someone in to check it. He said there was nothing wrong with the furnace and adjusted the thermostat. Everything seemed ok for a day and then it started again. The thermostat says that it is 66 degrees in the house, we have it set at 72, and it still won't kick on until we set it to 74 degrees. When it kicks on, it will not shut down on it's own. The house gets very warm and the temperature in the house keeps climbing clear up to 80 or 82 degrees,even though we only have it set on 74 degrees, and then we have to turn it off because it won't turn off on it's own. I do have someone else coming to check it again on Monday but if anyone has any advice or thoughts on what the problem could be, I would appreciate it. Thanks!