I have a Lennox gas furnace with central AC. I just lit my pilot and thought it was working fine, but noticed my furnace blower was coming on and off prior to the temp getting to the set temp to ignite the heat. When the temp does reach the set temp my burners light followed by the blower. The burners then quit after about 5-7 min and the blower continues for an additional 3 -5 min. My concern is the blower is coming on before it reaches the desire heat/temp.