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From Humble Beginnings

The Trusted Family Owned and Operated HVAC Contractor in Knoxville, TN since 2000.

The experts at A1-Certified Service, Inc. in Knoxville TN have given our customers comfort and peace of mind. We began in the late 1960's when cooling your home was in its infancy. Tom Thomas opened his doors to provide comfort to the homeowners in Central Florida. In the 1990's, Tom moved to Knoxville, TN, and has been serving the Knoxville & surrounding communities since! In 2012, Tom released the reigns of A-1 Certified Service, Inc. to his daughter, Michele Thomas. Michele is continuing the legacy and realized the importance of home performance and it's direct impact on the heating and cooling of the home. Today, she is providing the highest quality of air conditioning. heating, and home performance services and ensuring each customer receives the comfort and lower utility bills they deserve. 

Providing Quality Service for Your Comfort for Over 25+ Years 

Our Commitment to Our Community 

A-1 Certified Service, Inc. is committed to serving our community. We support our community through donations and volunteering at our local schools, charities, and Habitat For Humanity. We are proud partners with the TVA EnergyRight. For both retail and their Home Uplift Project, The Home Uplift project covers a multi-regional area and provides limited-income homeowners with energy-efficient upgrades to reduce their utility bills, their carbon emissions, and to elevate the strain on our current electrical grid structure. 

A-1 Certified Service, Inc. is also a humble sponsor of the Community Coalition Against Human Trafficking (CCAHT) Michele Thomas, the owner of A1CSI is passionately involved in this organization to lift up those in need as part of her mission in life. CCAHT was established in 2010, the Community Coalition Against Human Trafficking unites and equips Knoxville and all of the counties of East Tennessee to end modern-day slavery through awareness, training, and intervention, while also providing survivors of human trafficking in our community with a safe place to sleep, access to medical care, ongoing counseling, and more. Together, we believe we have the power to make our community stronger, safer, and free of exploitation – for everyone. To learn more, visit ccaht.org.