Nasons installed my central AC 20 years ago. They have made several repairs in that time, mostly start capacitors. However cost to install a new AC coil in the air handler was expensive, about $1k, which is typical cost for this repair. The AC Technicians are always prompt and make repairs quickly. Repair charges are fair. Best of all, my two 20 year old AC systems have made it thru another summer season on Aquidneck Island without any issues (change the filters beginning of summer, Its easy, and you can avoid some service calls!!!).