Our Certifications Our team at Klaus & Sons Heating & Air Conditioning in Upland works hard to offer the finest heating and cooling service around. One of the ways we sustain our expertise and continue to build knowledge about HVAC products is by earning industry certifications. Discover more about the certifications our experts have received below. North American Technician Excellence (NATE) NATE is North America’s largest non-profit heating, ventilation, air conditioning and refrigeration certification organization. NATE certified technicians perform excellent installation and maintenance on your heating and cooling systems. These technicians have proven their knowledge in the HVAC specialty areas including: Air conditioning Air distribution Heat pumps Gas heating Oil heating Hydronics gas Hydronics oil Ground source heat pump loop installer Senior HVAC Efficiency Analyst 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 Upland has partnered with Lennox®, a top name in home comfort, to offer some of the most innovative and energy efficient heating and cooling products in the industry. To keep “Premier” status, Klaus & Sons Heating & Air Conditioning participates 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. Better Business Bureau Klaus & Sons Heating & Air Conditioning is a member of the Better Business Bureau. That means we abide by ethical business behaviors and provide trustworthy information to our customers. We have a good rating and are proud to be part of this organization.