We recently purchased a 30 year old home (with 30 year old ducts and some units close to that). The owner of Longton Air (Bill MacDonald) personally inspected our units, ran a check of our duct work (which proved to look scary) and made recommendations depending on how aggressive we wanted to be to get to the most efficient system. Mr. MacDonald immediately sent pricing and answered all questions promptly and fully (his knowledge of his products is impeccable!). Mr. MacDonald gave us a couple of different options and his answers were in terms that we could easily understand to make an informed decision. The work was scheduled promptly and completed quickly. Many times Mr. MacDonald made the decision to replace aging duct work (at no additional cost) and used state-of-the-art accessories (thermostats, etc) that will add to our energy savings. We can not more highly recommend this company. Jill and Vic Zanetti Plano, Texas