MRCOOL MGM80SE090C5A 5 Ton Upflow/Horizontal 5-Speed Gas Furnace (MGM80SE090C5A)MRCOOL MGM80SE090C5A 80% AFUE 5 Ton 90,000 BTU Upflow Horizontal 5 Speed Gas Furnace When harsh winter weather strikes, nothing compares to the warmth and safety a powerful reliable gas furnace can provide. While furnace heating technology has been around for decades, not all systems are created equally. Some are definitely better than others. One of the best on the market is the MRCOOL single stage, 80% AFUE gas furnace. This system can be installed