What is the SEER rating of the Trane XL 1200?

What is the SEER rating of the Trane XL 1200 is 10 to 12 SEER depending on exact model and age, as it is an older unit manufactured in 1990s and early 2000s before higher efficiency standards. Trane XL 1200 was popular residential line produced from about 1992 to 2005, with models like TTP036C100A and TTP060C100A, and was rated at 10 SEER minimum when first introduced to meet 1992 DOE standard, and later versions up to 12 SEER after 2000, which was considered high efficiency at that time but is now considered low efficiency compared to current minimum 14 SEER in North and 15 SEER in South required since 2023. SEER stands for Seasonal Energy Efficiency Ratio and measures cooling output per energy input, so XL 1200 at 10 SEER uses about 40 percent more electricity than modern 14 SEER and about 60 percent more than modern 16 SEER to produce same cooling. If you still have Trane XL 1200 operating today, it is likely 20 to 30 years old and past its average lifespan of 15 to 20 years, and replacing with modern 16 SEER Trane XR16 can save 300 to 500 dollars per year in electricity in hot climate, paying back replacement cost in 5 to 8 years. The XL 1200 used R-22 refrigerant that is now phased out and expensive at 100 dollars per pound.