Back in the “good old days,” controls were all analog and mechanical, which simply means that they acted in a directly connected and variable manner based on a change in force. Both pneumatic (air pressure) or hydraulic (fluid pressure) systems are examples of mechanical or analog controls. When the pressure increased or decreased on a […]

In residential air handler/fan coils, it is common to use a high-voltage interlock between the blower and the electric heat strips to ensure that the blower comes on whenever the heat is on. The problem is that it CANNOT work the other way around where the heat comes on with the blower. Heat strips are […]

Bert recently made a video about his top residential A/C maintenance service tips. He showed some pretty good practices in there, so we’re going to revisit them in this article. Maintenance procedures are vital to any HVAC business, especially those specializing in residential A/C. When we do maintenances, the customers see our faces, and when […]