I first used ACS a few years ago when I heard popping noises and smelled smoke coming from my 20 plus year old ac. Even tho it was Saturday and a holiday weekend, they came out and had my system back running with no smoke or strange sounds within the hour and at a very reasonable rate. They recommended I start thinking about replacing it since it was so old and limping along. It worked ok for another almost 2 years, and when I decided to replace the unit, I called ACS again and they put a new system in. I am pleased with their courteous, prompt, competent service, competitive pricing, and I love that my utility bills have been $50 or so less each month! I probably should have had them replace it the first time out, and I would definitely recommend these guys to my friends and family.