It’s expensive to run a business in California. That’s why lowering the energy costs of your air conditioning and heating equipment is so important. If your HVAC equipment is bigger than five tons, then a VFD may be just what you need. VFDs, or variable frequency drives, can save you money on energy bills and motor repairs. With an average of two years return on investment, and rebates available from California utility companies, you don’t want to miss out on a great way to save money.

Variable frequency drives are basically speed controllers for your AC motors. HVAC motors can come in one, two or three speed options. Single speed is typical for the average small-to-medium commercial unit. VFDs actively adjust a motor’s rate depending on the site’s load. For example, if the outside temperature is cool and your office is comfortable, a VFD will adjust the motor speed down to reduce energy usage.

Example of a VFD.

To use a VFD properly requires a controller, a user interface, the motor, and a power source. In the case of a VFD we’re utilizing electricity, since this removes the need for an additional mechanical part such as an inverter. Fewer mechanical parts reduces unexpected failure chances.

The controller is wired into the unit and communicates with the user interface. Typically, this is a monitoring program that can provide plenty of information about your system, such as current space temperature, any active alarms, and most importantly access to the VFD. From here you or your technician can apply the appropriate programming.

Why Use It?

Once your VFDs are installed, the energy savings can begin. Dropping the fan speed by 30% on 1st stage cooling and ventilation is a simple set-up that can start showing results right away. And even these simple settings can reduce fan energy usage by at least 27%, all the way up to 69%. If you’re planning on replacing your units, you can have VFDs come pre-installed on any units over 7.5 tons, by requesting the systems be “Title-24 Compliant”.

Of course, VFDs aren’t just for new units. Utility companies like Southern California Edison are ready to offer incentives to get your older units outfitted. Systems with more than a few years of use left can benefit from VFDs just like brand-new units can. A VFD can improve the lifespan of aging units, squeezing out a few more years before they have to be replaced. And if you’re determined to get your energy bill down, a VFD is an affordable alternative if full system replacement is currently out of the question.

It’s not just energy you save with a VFD, but wear and tear on your HVAC motors. For starters, with a variable speed drive installed, the controller can initiate a “smooth” start. This can ease the repeated strain of hard starts and extend a motor’s lifespan. A VFD also helps eliminate mechanical vibrations*. Unnecessary vibration can cause a motor to breakdown over time. Adding an AC drive can direct the motor to bypass certain speeds that cause that unnecessary vibration.

VFDs offer an affordable, smart solution to your high energy bills. With the newest models designed for optimum efficiency, you are sure to see a return on your VFD investment. Your motors will love the extra care you’re giving them just by reducing their overall run-time. And if you’re curious about more ways to say energy with your AC units, check in with us next month for a run-down on HVAC controls, how they work, and why you should consider them for your business.