DUCTZ uses the Ductbusters patend process to clean your HVAC system. DUCTZ owns the patend. DUCTZ of Maryville - Southern Knoxville are proud members of NADCA (National Air Duct Cleaners Association) and the BBB. We pride ourselves in educating our customers about HVAC system cleaning. State licensed with the Tennessee Dept of Agriculture to use EPA registerd chemicals in HVAC systems to control microbial growth. State charter number is 4377. We do residential and commercial cleaning. NADCA certifications ASCS (Air System Cleaning Specialist) and VSMR (Ventilation System Mold Remediation). Offer free assessments to provide a acurate estimate of what your HVAC system needs in cleaning, sealing, and insulation.