About Cool Tech Heating & Air Conditioning We always answer the phone – Day or night, 365 days a year, your call will always be answered by a Cool Tech employee. We do what we say we are going to do – Our professional, prompt technicians will arrive when we promise. With our flat-rate pricing, you always know the price before we do the work. No hidden costs, no extra fees. We charge a diagnostic fee not a service call fee so no matter where you are at in the Charlotte, NC area you don't pay any extra. We surround ourselves with the best people – We hire professional employees that are willing to help our customers no matter what. With their “whatever it takes” attitude, you can rest assured that we’ve got you covered.