My American Standard Allegiance-12 was installed during new home construction in late 1997 along with an American Standard Freedom-90 gas furnace, and did a pretty good job until it developed a condenser coil leak in September 2010. The leak turned-out to be a manufacture defect in the outdoor aluminum coils. The machine that spirals the tines onto the coil during manufacturing was maladjusted and scored the coil causing a weak spot in the line. Over time and vibration, the score ruptured… Leaking the r22 refrigerant. I was able to unconventionally, but effectively repair that leak. However, now we have a new leak too small to detect in another location of the coil… And r22 has tripled in price. The hvac industry has proven that they can build units that will last 18 to 25 years, now they've doubled the price, lowered the quality of materials, and all of this at a time when systems require "high pressure 410a" quality. So much for going "Green" with a good carbon footprint. The new American standard is that quality is inversely proportionally to price. P.S. American Standard furnace blower motor housings are as flimsy as they can get.