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Coffee Break with Travis Starns from Blender Products

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How Does a Channel Blender Improve HVAC Performance?

That’s the question we asked Travis Starns, VP at Blender Products, at our most recent Coffee Break webinar. These 50-minute sessions earn attendees 1 PDH and give them an insider look into the most cutting-edge technologies and solutions in the world of HVAC. Ask your SVL Sales Engineer for an invite to our upcoming sessions.

The Problem of Air Stratification

Blender Products engineers solutions to combat the problem of air stratification in AHU mixing boxes. When two airstreams, the outdoor air (OA) and return air (RA), mix in an AHU, the resulting combined airstream is rarely uniform. It has hot and cold zones, and variable velocity and moisture content.

Temperature stratification in AHUs is a well-known problem. It leads to freeze-stat trips and frozen coils, and those repairs can be costly. Uneven moisture loading in the airstream can result in condensation and mold growth.

To extend economizer operations and ensure the highest performance of your AHU, improving the air uniformity coming out of the mixing box solves several potential problems. ASHRAE notes that good air mixing is essential for proper coil operation (Chapter 27, Section 2). Several mixing boxes, especially on older equipment, just don’t do an effective job.

What strategies exist to combat air stratification?

Some designs attempt to orient the dampers such that the airstreams mix on their own. The modeling data shows this strategy doesn’t usually work well. Air only remains in a mixing box for a fraction of a second—this isn’t much time for the airstreams to mix effectively. The RA will form a thermal barrier rising against the colder OA, and relatively little heat transfer will occur.

Another field fix is to install a baffle plate in the mixing box to direct the outdoor air directly in front of the return air dampers. This works a little better, but still has plenty of issues. It often creates greater velocity stratification in the mixing box, and it doesn’t address the root cause of poor stratification inside the unit.

What about a static blender?

Blender Products’ benchmark technology is the Series IV Air Blender. It does a fine job of combatting stratification, but it comes with trade-offs. The increase in pressure drop is significant, and it adds 43” of additional space to the mixing box. The feedback from engineers has always been that they love the mixing capabilities of the Series IV but say it’s hard to find 43” of extra space in the mechanical room.

How does the Channel Blender improve on the Series IV blender?Blender-Products-Channel-Blender

Introduced in 2018, the Channel Blender is a response to those space constraints, offering the same freeze protection without the added footprint. It eliminates the blender section of the AHU while providing the same level of mixing. It raises the minimum temperature before the coil above the freeze-stat threshold of 37–38 °F while needing only 8” of space for effective mixing.

Saving length means saving real money in AHU operations. Channel blenders replace traditional dampers and cabinetry, making them a great choice for retrofits that can’t accommodate more space for mixing.

How does it work?

The Channel Blender comprises a series of sheet metal channels that replace traditional dampers. The damper sections for the OA and RA streams are oriented into alternating channels that feature dual skin walls with insulating media in between. These channels create micro-collisions of airstreams that create a uniform mixing field just beyond the dampers.

What are some other benefits?

Protecting against freeze-stat conditions and extending economizer operations are only two of the benefits the Channel Blender offers:

  • It features integrated, independently controlled OA and RA dampers for pinpoint accuracy on the mix of airstreams your application requires
  • It is a custom-designed piece, and designs can fit almost any mixing box and orientation of incoming airstreams
  • It prevents velocity stratification, improving the performance of downstream filters
  • It improves coil performance through reduced variability of moisture in the airstream

Custom engineering reports are provided for each Channel Blender installation

Interested in More?

Learn More About The Channel Blender
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                      Jim Lubratt

                      President & Chief Executive Officer

                      Jim Lubratt has been president of SVL since 2006. He first joined the company as a sales engineer in 1992 and was made a partner in 2000. He holds a Bachelor of Science in mechanical engineering from Southern Methodist University and first entered the HVAC industry as a marketing engineer for a heat pump manufacturer in Texas.

                      In addition to his role at SVL, Jim is vice president of AQC Industries, LLC, a manufacturer of specialized underground ductwork systems. He is also an investor and board member for Hydromx, Inc., a manufacturer of heat transfer nanofluids, and Crotega, Inc., creators of personal and building security solutions.

                      Jim and his wife, Tracy, met in college and married in 1993. They have three children, two of whom have graduated college in Texas, while their youngest is attending Grand Canyon University in Arizona.

                      Outside of work, Jim places a priority on his faith, family, friends, and fitness. He enjoys helping people-supporting charities, time with his wife and kids, road-biking with friends and efforts to stay physically fit.

                      A message from Jim on the achievements of SVL

                      SVL started in February 1967 by Charlie Schwab and Craig Vollhaber. Schwab-Vollhaber, Inc. (as it was named at the time) steadily grew and, in 1985, welcomed Paul Lubratt as another partner, becoming Schwab-Vollhaber-Lubratt, Inc. SVL’s founders had the determination to build the most talented, customer-focused HVAC representative in the Midwest. Our original drive and passion still shape the company and culture to this day. The achievements of an organization are the results of the combined efforts of every individual. From humble beginnings, SVL founders paved the way to industry success with hard work and determination. “Today, SVL is strongly organized with great people to lead our industry forward as we are challenged with fast-paced changes to reduce our environmental impact,” says Jim. Now, 55+ years later, SVL is under the leadership of two new principals who share the same vision and drive that has propelled SVL throughout the years. Built on a foundation of integrity, Jim Lubratt, and Charlie Vollhaber strive to ensure opportunities for personal growth, improved work environment, and shared life enrichment. The achievements of our organization are the results of the combined efforts of every individual.

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                      Charlie Vollhaber

                      Executive Vice President & Officer

                      Charlie Vollhaber is a third-generation employee at SVL, as a grandson of company co-founder Craig Vollhaber and son of former CEO Todd Vollhaber. Charlie holds a Bachelor of Science in mechanical engineering and an MBA, both from the University of Minnesota. He became an outside salesman for SVL in 2013, was made a partner in 2019, and then executive vice president and officer in 2022.

                      He grew up playing sports, including football, basketball, golf, and track, and enjoys the competitive nature of the HVAC industry. “I like that no two days are ever the same as there are always questions to answer and problems to solve,” he says. “Most of all, I enjoy working with great people and coordinating together on challenging projects to achieve positive results together.”

                      Outside of work, Charlie enjoys spending time with his wife, Lesley, and their three boys. He’s also fond of golfing, traveling, and attending concerts and sporting events. One of his favorite quotes is from the book of Philippians: “Do nothing from selfish ambition or conceit, but in humility count other more significant than yourselves. Let each of you look not only to his own interests, but also to the interests of others.” Because HVAC and construction is such a team effort, he says, “this mindset helps to create positive results in a vast majority of situations.”

                      A message from Charlie on the culture of SVL

                      “At SVL, we strive to cultivate a unique culture that revolves around finding and empowering exceptional individuals. We believe in equipping our team members with the right tools and resources to succeed.

                      As we’ve grown the business, we have deliberately maintained a small firm culture, fostering an environment where collaboration thrives. We encourage open dialogue and promote a sense of comfort among our employees, allowing anyone to ask questions and seek guidance from anyone else, regardless of their level within the organization.

                      We foster a workshop-like atmosphere where everyone’s contribution is valued. Presenting your work to another individual or a group of teammates provides a platform for collaboration, where ideas are shared, dissected, and improved collectively. We firmly believe in the power of mentoring and provide various avenues for both formal and informal guidance. Whether it’s through structured training programs or casual conversations, we encourage team members to discuss a wide range of topics, from work-related successes or issues to everyday personal life topics.

                      In summary, our culture is built on the foundation of attracting exceptional individuals, empowering them with the necessary tools, and fostering a collaborative environment where mentorship and growth thrive. We are committed to creating an atmosphere where every team member feels supported, valued, and encouraged to reach their fullest potential.”

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                      Al Gramse

                      Vice President of SVL Service Corporation

                      Al Gramse has been in the HVAC industry for over 30 years. He began as a service technician.  Then over his career worked in technical support, building automation, then service manager prior to his current role.

                      How did Al end up in the HVAC industry?  “After high school, I took a couple years to figure out what I wanted to do.   Where I was working at the time, a grumpy old coworker, who I didn’t get along with, walked up to me and said ‘What are you doing here?  Go back to school.’”  I said, “For what?”  He said “There’s a tech school down the street.  Go down there and pick something that interests you”. Then he walked away.  That weird interaction, with someone I didn’t get along with, sent me down a 30-year path in the HVAC industry.   Never underestimate the potential of a little encouragement.   Even if it is from a strange source.

                      Al has been with SVL for 15 years and is the head of our SVL Service division. “The people here are some of the best in the industry,” Al says. “A bunch of team-oriented, knowledgeable, go-getters.” His personal mantra is “figure it out,” “Do a little fact-finding on your own. Use your own brain before you use someone else’s. But know when to ask for help.” he prescribes. “It’s amazing what you can accomplish on your own if you dig in a little bit.”

                      Outside of work, Al has lots of outdoor hobbies, including hunting, fishing, and motorcycling, though his favorite pastime is simply hanging out with family.

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                      Jennifer Roach

                      Director of Marketing, Events & Administration

                      More than just a creative director, Jen brings 30 years of marketing and leadership magic to SVL. Her journey began in the trenches of graphic design, quickly evolving into crafting eye-catching campaigns for iconic brands like Target, Gabberts, Gander Mountain and Camping World. As a seasoned director and agency veteran, she honed her skills with recreational vehicle giant Parts Unlimited before leading creative teams at HOM Furniture and, ultimately, landing at SVL during a crucial growth phase.

                      Jen thrives on "servant-leadership," empowering her team and fostering a culture of trust and mutual respect. "It unlocks their potential, fuels creativity, and leads to work we're all proud of," she says. "I want my team to care, collaborate, and push boundaries together."

                      When not shaping impactful campaigns, Jen enjoys weekend adventures with her husband, Scott, and son, Crew. Their lives are a tapestry of shared passions, from bike rides and baking experiments to cheering on Simley High School wrestlers. And with her recently built forever home in Cottage Grove, her free time now includes a new, thrilling chapter: weekend renovation warrior!

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                      Mike Ruff

                      Vice President of Information Technology

                      Mike Ruff, the Vice President of Information Technology at SVL Inc., is a seasoned professional with an impressive 24-year tenure in the IT industry. His journey in the field is marked by extensive experience and expertise in various domains, including serving as a Cloud Architect focusing on Azure Software as a Service (SaaS), Infrastructure as a Service (IaaS), and both B2B and B2C solutions. Mike’s skills extend to being a Security Architect, where he has honed his knowledge in safeguarding digital assets, and he is also proficient in the Microsoft 365 stack, virtualization, routing, switching, and wireless technologies.

                      Beyond his professional roles, Mike is deeply passionate about technology in all its forms, which is evident in his career and personal hobbies. His love for technology is not just limited to his work but also spills over into his leisure activities. In the summertime, Mike enjoys the thrill of riding his motorcycle, embracing the freedom and adventure it brings. When winter arrives, he switches gears to snowboarding, seeking the excitement and challenge of the snowy slopes. These hobbies reflect Mike’s dynamic personality and continuous pursuit of technically engaging and physically exhilarating activities.

                      Mike Ruff's blend of professional expertise and personal passions make him a unique and valuable asset to SVL Inc., embodying a perfect synergy of technical acumen and a zest for life's adventurous aspects.

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