Thermometer Central stocks Aprilaire brand products for ventilation, filtration, and purification. Aprilaire develops innovative indoor air quality solutions including ongoing programs of testing, engineering, research, product refinement and practical experience. As a leader in the Heating, Ventilation and Air Conditioning (HVAC) accessories industry, Aprilaire is able to work closely with associations such as the Air-Conditioning and Refrigeration Institute (ARI) and the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE).