Did you know that industry experts in the area of energy management and maintenance (not heat/ac experts) recommend replacing your heating and cooling equipment every 10 to 12 years. This Rule of Thumb considers technology and energy efficiency advancements, which also improve comfort and air quality. Replace equipment with the most efficient equipment you can afford, they further recommend. Paybacks tend to average 7 to 9 years on the new equipment, when energy savings is considered.