Indeeco - Explosion-Proof Duct Heaters

Ultra-Safe™

Explosion-Proof Duct Heaters

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Ulta-Safe™

Engineering developments at Indeeco have made explosion-proof duct heaters for hazardous locations readily available at affordable prices.

  • CSA-approved for virtually all Class I and Class II, Division 1 and 2 hazardous gas or dusty atmospheres
  • Ignition temperatures as low as 320 °F (160 °C)
  • Six standard sizes to fit a wide range of ducts
  • Ratings up to 240 kW, 600 volts
Standard Construction
  • Heat Exchanger: copper tubes with integral aluminum fins. Each unit undergoes hydrostatic testing at 350 psig, five times the pressure relief valve setting of 70 psig.
  • Heat Transfer Fluid: propylene glycol, a nontoxic, rust-inhibiting fluid that provides freeze protection to -49 °F (-45 °C). Its high heat transfer rate at 70 psig makes the heat exchanger suitable for gases that ignite at temperatures as low as 320 °F (160 °C). Thus every Ultra-Safe heater is rated for Temperature Code T3C.
  • Industrial Grade Heating Elements: built by Indeeco, .475″ (1.21 cm) diameter to provide extra insulation between the coil and sheath for high voltage protection.
  • Frame: heavy gauge galvanized steel, fitted with lifting lugs to facilitate installation.
  • Four Levels of Safety: Every heater has automatic and manual reset thermal cutouts, airflow interlock, and pressure relief valve. Two thermal cutouts limit the heat transfer fluid temperature. The automatic reset operates a “primary” magnetic contactor, and the manual reset uses a separate backup magnetic contactor. If either cutout opens, the entire heater is de-energized. A fan relay, acting as an airflow interlock, prevents the heater from being energized unless the fan starter is on. The pressure relief valve on the heat exchanger opens only if the thermal cutout system fails to prevent excessive temperatures.
Standard Built-in Control Package

The following components are mounted in a cast aluminum explosion-proof enclosure:

  • De-energizing control and backup magnetic contactors
  • 24V control circuit transformer
  • Fan relay, supplied with 24V or 120V holding coil to match the fan starter coil voltage
  • Terminal blocks for field power and control wiring
  • Grounding terminal
  • Supplemental fusing for heaters drawing more than 48 amps

Series EP

Explosion-Proof Duct Heaters

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Series EP

Engineering developments at Indeeco have made electric duct heaters for hazardous locations readily available at affordable prices.

  • CSA Approved for Class I, Division 2 locations where a hazardous gas is occasionally present
  • Ignition temperatures as low as 392 °F (200 °C)
  • For ducts up to 240″ (610 cm) wide by 120″ (305 cm) tall
  • Ratings up to 1000 kW, 600 volts
Standard Construction
  • Galvanized Sheet Metal Frame: includes external flanges for field mounting and an element terminal box. Terminals are factory-connected to control safety components in an integral cast aluminum explosion-proof box.
  • Three Levels of Safety: Every heater includes automatic and manual reset thermal cutouts, plus a fan interlock relay. The automatic reset cutout, operating through the temperature control system, is the primary protector. The manual reset operates a separate backup magnetic contactor independent of the temperature control system. The fan interlock relay prevents the heater from being energized unless the fan starter is on.
  • Industrial Grade Heating Elements: built by Indeeco, are .475″ (1.21 cm) in diameter to provide extra insulation between the coil and sheath for high voltage protection. Stainless steel fins are helically wound onto the stainless steel sheath.
Standard Built-in Control Package

The following components are mounted in a cast aluminum explosion-proof enclosure:

  • De-energizing control and backup magnetic contactors
  • 24-volt control circuit transformer
  • Fan relay for heater/fan airflow interlock. Supplied with 120V or 24V coil to match the fan starter
  • Terminal blocks for field power and control wiring
  • Grounding terminal
  • Supplemental fusing for heaters drawing more than 48 amps

Custom

Explosion-Proof Duct Heaters

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Custom Explosion Proof Duct Heaters

Indeeco generally constructs heaters per Series EP2, except with element terminals and control components built into a cast aluminum explosion-proof enclosure.

Standard Construction:
  • Frame: sized to fit the duct. Slip-in is also available, if necessary, to match other equipment. Galvanized steel standard; stainless steel optional.
  • Control Enclosure: NEMA 7, 9 cast aluminum box with hinged cover houses controls and element terminals. Weatherproof construction is optional.
  • Heating Elements: heavy wall, large diameter stainless steel finned tubular elements, individually removable for servicing.
  • SCR Temperature Control: SCRs with zero-cross firing provide precise proportional control. SCRs also minimize element operating temperatures for extra safety. Optional on/off single or multi-stage control is also available.
  • Overtemperature Protection: Thermocouple controllers measure element sheath temperature. Automatic reset control resets when the temperature drops to a safe level. Manual reset control, with an external button, provides backup protection.
  • Fuses: individual circuit fusing for heaters drawing over 48 amps to meet NEC requirements.
  • Airflow Interlock: The fan relay prevents heater operation unless the fan becomes energized. Built-in or remote explosion-proof airflow switch is optional.

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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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