I was a customer of C&D Cooling and Heating a couple years ago and they worked on my furnace. I was very happy with that experience. Then I called this other contractor recently looking for someone to do work on my AC unit and he recommended I try C&D. I said I had worked with them before and I gave them a call. The problem was that our AC wasn't keeping up with our cooling needs during a couple of days when it was really hot. The technician from C&D came out and checked the refrigerant level and found it to be a couple pounds low. He also injected some leak-stop fluid right where the refrigerant goes that will discharge a blue color if there are any leaks. Overall the job came to about $1000, which was more than I wanted to pay, but it was worth it for the service. I was very pleased.