HOFFMAN UNFILTERED
Educational Blog Content for HVAC Professionals

A Variable Speed Drive (VSD) is a device used to vary the speed, or RPMs of an electric motor. The most common motor in use today is the AC induction...

A variable frequency drive (VFD) controls an electric motor by varying its voltage and frequency. Also, a VFD can control the ramp-up and ramp-down...

There are many reasons why electric motors fail, resulting in unplanned and expensive system downtime. Maintenance issues like over-lubrication,...

We are huge proponents of continuing education.  In the commercial HVAC world, technology is changing. We, as system designers, building owners,...