[Editor’s note: When we last visited with lead installer John and his helper Charlie (in the June 11 issue), they had learned how to measure external static pressure on a new system they had just ...

GET IT RIGHT: Duct fitting construction has a large influence on its equivalent length and which air duct calculator setting you choose. The fitting on the left has a much higher equivalent length due ...

Developers and owners of residential homes are generally keen on keeping heating and cooling costs as streamlined as possible without sacrificing performance. A properly sized system costs less to run ...