The air conditioning unit on the second floor of our home went out this past weekend when things were getting warm. I called Comfortmaster Heating & Cooling Services and their 24-hour service line and within about an hour and a half, one of their technicians was here. He worked for two hours and completely solved the problem our unit was having. I couldn't have asked for a better experience. We have been using Comfortmaster for 15 years now, and I love their responsiveness. Their crew members are very pleasant and professional, and we have been particularly impressed by Bob Montero and Rob, the tech who came out this past weekend. They do a great job, and I will not stop using their services.