With an AFUE up to 95%, the K2™ condensing boiler does an outstanding job of establishing a balance between high-efficiency and high value. This is achieved by mating the proven and reliable performance of a high-efficiency heat exchanger with the Sage2.2™ control system. The impressive list of high-value standard features that come with the K2™ boiler adds to the overall savings that it can provide. The K2™ is also wall-mounted, offering a space-saving, low depth profile that is tremendously flexible in tight installation spaces.