We've been using Crystal for our heating and air conditioning system for years, mostly for our semi-annual checkups. We've had Darren H come out a number of times. I have always found him professional. He shows up when he says he will, he gets down to work and he communicates clearly about what he found with our system. This time, we needed to replace a small part in our AC system and he explained the part and why we needed to replace it and showed us how the part of deficient. Because we've had a relationship with Crystal and Darren for so long I had no doubt that if he said we needed to replace the part, we needed to do it. He made the repair quickly and the cost was extremely reasonable. As long as we live in the area, we will be giving our heating and AC business to Crystal.