Built with durable materials and powered by advanced technology, Armstrong Air furnaces have been the smart homeowner's first choice for heating equipment since 1928. But what is it that separates Armstrong Air furnaces from others? It's true American craftsmanship. Armstrong Air furnaces are developed and assembled in Orangeburg, South Carolina and tested extensively before they reach the hands of our expert technicians. This helps ensure that they continue working hard to provide dependable warmth one winter after the next. Furthermore, many of these furnaces come equipped with variable speed blowers for increased efficiency, quieter operations and more consistent comfort.