About A-1 Certified Service, Inc.
A-1 Certified Service, Inc. is a full-service HVAC, insulation, and Home Performance company serving the Knoxville area. Customers have expressed great satisfaction with the company's professional and personable technicians, who are experienced, courteous, and knowledgeable. The technicians communicate well, work hard, and are dedicated to providing exceptional service. Customers have found the company to be reliable and have used their services for both personal and business needs, always receiving professional and quality work. The company has consistently received excellent reviews from customers. Technicians like Zachary Ian Staggs have been praised for their professionalism and expertise in repairing and servicing HVAC systems. Customers have been very happy with the technicians' ability to diagnose and fix issues, as well as their clear explanations of the work done. The company is highly recommended for HVAC repair, replacement, and installation services.
A-1 did a great job working with us to find a unit that met our needs. Scheduling was fast and the front office was really good at communicating everything. Our technician was fast and clean, going so far as to cover and tape all the clothes in the closet before going into the attic. I'd definitely recommend them!
Considering the challenges that the installers faced with this property, they did a good job. Duct work was repaired as well as the addition of new ducts through difficult situations. However the job was left incomplete as grills for the new floor vents were forgotten. Weeks later I received the grills in the mail.
HVAC quit operating 12/12/25 and thermostat went dark. Zach was sent out that afternoon. He quickly found the problem. It was a faulty ultraviolet light and ballast. He removed it and bypassed it in the circuitry. He didn’t have the part so Michelle at the office called and said that it would be installed on Tuesday, 12/17. Very timely resolution.
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The technician, Jimmy, was prompt and professional. He sent emails to let me know he was on his way. He came and went straight to the unit did the examination and brought the problem to my attention. Since the problem was a light that had been installed on my unit recently, he was going to try to get it to the warehouse where they got bought it from to see if there was any restitution either with a new light since it hadn’t been that long of a time span or give me a credit. Very courteous and professional. A1 Certified is the best!