Our Certifications at M & S Heating & Air LLC Our team at M & S Heating & Air LLC in Mechanicsville aims to have the finest heating and cooling service around. One way we sustain our expertise and continue to learn about HVAC products is by earning industry certifications. Discover more about the certifications our experts have received below. Dave Lennox Premier Dealer™ Dave Lennox Premier Dealers™ are specially trained and independently evaluated regularly to offer a higher level of customer service. As a Dave Lennox Premier Dealer™, our team in Mechanicsville has partnered with Lennox®, a top name in home comfort, to provide some of the most innovative and energy efficient heating and cooling products in the industry. To keep “Premier” status, M & S Heating & Air LLC takes part in an independent Customer Review program that encourages our clients to honestly rate our performance so we can make sure our staff continuously is meeting or exceeding the highest standards for quality service.