A variable frequency drive (VFD) fails to vary the discharge-air fan speed. A motor overheats and fails prematurely. While each troubleshooting problem in an HVAC system presents its own unique set of ...

To minimize motor imperfections, contractors must stress the importance of a comprehensive inspection, properly identify and diagnose the root cause of the deficiency, and be able to explain the ...

Last year, the plant upgraded a large, critical motor system by adding a variable frequency drive (VFD). The main impetus for this decision was to stop the damage from across the line starts, an ...