I purchased my 2012 Elkridge 35 QSQB used in April 2012. No warranty due to being second owner. Fought furnace until October when repair shop finally found 2 heat ducts forced through a hole in wall large enough for 1 duct causing overheating of furnace which shut down after 1 to 3 cycles. After enlarge hole in wall seems to work fine. Has anyone else had this problem. Apparently poor work at factory. Spent about $5OO total on 3 different repair bills before finding real problem.