ATH - Advanced Thermal Hydronics Hot Water Boilers

KN2

KN Series Boiler

For More Information:
ATH-KN2-Boiler

Condensing, High Efficiency: 200,000 Btu

The Energy Star-rated KN2 cast iron boiler is ideally suited for residential and light commercial boiler applications, including new construction and retrofits. With a maximum output of 200,000 Btu and capable of modulating down to a 40,000-Btu minimum, the compact footprint of the KN2 makes this cast iron condensing boiler the ideal choice for hydronic space heat, radiant heat and snow-melting applications.

And don’t let its size fool you, the KN2 is built with the same quality, durability and levels of efficiency as the larger ATH KN-Series boilers. Constructed with the signature KN Series cast iron heat exchanger, the KN2 offers unrivaled heat retention, resulting in lower operating costs.

Features and Benefits That Come Standard

  • 5x more wall thickness than stainless steel and aluminum
  • Low NOx & CO2
  • 90% AHRI-certified efficiency
  • Accepts 10:1 range of water flows (variable volume systems)
  • Tru-Flow Advanced Air/Fuel Delivery System
  • 25-year heat exchanger warranty
  • 100 psi maximum working pressure
  • Assembled boilers use 80% post-consumer recycled materials
  • LEED-qualified
  • Plastic components are made from 40% post-consumer recycled materials
  • Factory piped and wired
  • HeatNet Control Platform with touchscreen
  • Vent/intake runs of up to 80 equivalent feet
  • Optional HeatNet Online Remote Monitoring
  • Natural gas/LP gas/dual fuel
  • 52″ x 29″ x 18″ HWD footprint

KN4

KN Series Boiler

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ATH-KN4-Boiler

Condensing, High Efficiency: 400,000 Btu

Featuring large Delta Ts and fully modulating 400,000 Btu the KN4 cast iron boiler is the best condensing boiler unit to provide solutions to a multitude of challenges, including the growing radiant heat and snowmelt markets and other new construction and retrofit boiler applications.

KN4’s small vent size also allows the utilization of existing vent work as a chase for new equipment in retrofit applications. Its small footprint makes incorporating its power into new constructions as simple as ever. With 92.7% thermal efficiency at full input and 99% combustion efficiency at minimum input (5:1 turndown), the KN4 is a high-efficiency condensing gas-fired boiler option. Additionally, the durable cast iron engineering behind the KN Series, when coupled with HeatNet 3.0 boiler control technology, makes for efficient fuel utilization and increased boiler performance.

Features and Benefits

  • Accepts 10:1 range of water flows (variable volume systems)
  • 25-year heat exchanger warranty
  • 5x more wall thickness than stainless steel and aluminum
  • 90% AHRI-certified efficiency
  • Tru-Flow Advanced Air/Fuel Delivery System
  • 100 psi maximum working pressure
  • LEED-qualified
  • Assembled boilers use 80% post-consumer recycled materials
  • Plastic components are made from 40% post-consumer recycled materials
  • Vent/intake runs of up to 80 equivalent feet
  • Factory piped and wired
  • Optional HeatNet Online Remote Monitoring
  • HeatNet Control Platform with touchscreen
  • Low NOx & CO2
  • Natural gas/LP gas/dual fuel
  • 52” x 36” x 22” HWD footprint

KN6

KN Series Boiler

For More Information:
ATH-KN6-Boiler

Condensing, High Efficiency: 600,000 Btu

With 600,000 Btu in a compact footprint, the KN6 features a fully modulating, cast iron design and boasts increased condensing efficiency when compared to common condensing, gas-fired boilers. Built strong to handle the increasing demands of today’s commercial boiler applications, the KN6 is an ideal choice for boiler operations within corporate office facilities and educational centers.

Designed for increased boiler performance and longevity, the KN6 was engineered with an ultra-efficient Tru-Flow symmetric air/fuel coupling design that burns clean while ensuring proper combustion at all firing rates, as well as 5:1 modulation for maximum efficiencies at all levels of heat demand.

Features and Benefits

  • 90% AHRI-certified efficiency
  • 25-year heat exchanger warranty
  • Optional 10:1 turndown
  • 5x more wall thickness than stainless steel and aluminum
  • Accepts 10:1 range of water flows (variable volume systems)
  • 100 psi maximum working pressure
  • Plastic components are made from 40% post-consumer recycled materials
  • LEED-qualified
  • Tru-Flow Advanced Air/Fuel Delivery System
  • Assembled boilers use 80% post-consumer recycled materials
  • Factory piped and wired
  • Vent/intake runs of up to 80 equivalent feet
  • Natural gas/LP gas/dual fuel
  • Low NOx & CO2
  • 72” x 36” x 43” HWD footprint
  • HeatNet Control Platform with touchscreen
  • Optional HeatNet Online Remote Monitoring

KN10

KN Series Boiler

For More Information:
ATH-KN10-Boiler

Condensing, High Efficiency: 1,000,000 Btu

Producing 1,000,000 Btu, the KN10 is engineered to meet the low fuel use, low installation cost and small footprint needs of today’s commercial boiler market. Like all ATH KN-Series boilers, the KN10 combines cast iron’s condition-tolerant and heat-retaining characteristics with full-modulating condensing boiler performance fuel savings.

The KN10 boasts 5:1 continuous modulation and can handle variable volume flows, resulting in one of the most flexible, innovative, and efficient boilers on the market.

Features and Benefits

  • 72” x 36” x 50” HWD footprint
  • Optional 10:1 turndown
  • 5x more wall thickness than stainless steel and aluminum
  • 90% AHRI-certified efficiency
  • 100 psi maximum working pressure
  • Tru-Flow Advanced Air/Fuel Delivery System
  • 25-year heat exchanger warranty
  • Accepts 10:1 range of water flows (variable volume systems)
  • Plastic components are made from 40% post-consumer recycled materials
  • LEED-qualified
  • Assembled boilers use 80% post-consumer recycled materials
  • Vent/intake runs of up to 80 equivalent feet
  • HeatNet Control Platform with touchscreen
  • Factory piped and wired
  • Natural gas/LP gas/dual fuel
  • Low NOx & CO2

KN16

KN Series Boiler

For More Information:
ATH-KN16-Boiler

Condensing, High Efficiency: 1,600,000 Btu

The KN16 produces 1,600,000 Btu while maintaining the features that have made KN Series boilers the most recognized line of condensing, gas-fired boilers in the commercial boiler industry; long-lasting durability and ultra-high condensing efficiencies, all in a compact footprint.

Capable of rising to the challenge of any commercial boiler application, the KN16 was engineered on the solid foundation of a high-efficiency, condensing boiler with a cast-iron heat exchanger. Paired with the state-of-the-art HeatNet 3.0 boiler control platform, Tru-Flow “whirlwind” blower and gas valve package that replace traditional VFDs, the KN16 delivers pinpoint modulation, ensuring maximum performance at any firing rate.

Features and Benefits

  • 72” x 35” x 60” HWD footprint
  • Natural gas/LP gas/dual fuel
  • Low NOx & CO2
  • HeatNet Control Platform with touchscreen
  • Optional HeatNet Online Remote Monitoring
  • Factory piped and wired
  • Vent/intake runs of up to 80 equivalent feet
  • LEED-qualified
  • Assembled boilers use 80% post-consumer recycled materials
  • Plastic components are made from 40% post-consumer recycled materials
  • 100 psi maximum working pressure
  • Tru-Flow Advanced Air/Fuel Delivery System
  • Accepts 10:1 range of water flows (variable volume systems)
  • 5x more wall thickness than stainless steel and aluminum
  • 90% AHRI-certified efficiency
  • 25-year heat exchanger warranty
  • Optional 10:1 turndown

KN20

KN Series Boiler

For More Information:
ATH-KN20-Boiler

Condensing, High Efficiency: 2,000,000 Btu

With an output of 2,000,000 Btu, the KN20 is built to withstand any harsh environmental conditions that come its way. Engineered with the signature KN Series cast iron heat exchanger and full-modulation condensing boiler performance, the KN20’s durability and reliability are second to none.

The KN20 enables low installation cost alongside optimal fuel utilization in a small footprint regardless of the boiler application size. When integrated with HeatNet 3.0 boiler control software, the KN20 can be used in conjunction with other KN Series boilers in a master/member network of up to 16 units and other units using HeatNet 3.0 software, creating a custom boiler network to meet the heating demands of the most extensive commercial boiler operations.

Features and Benefits

  • 72” x 35” x 67” HWD footprint
  • Optional 10:1 turndown
  • Plastic components are made from 40% post-consumer recycled materials
  • LEED-qualified
  • HeatNet Control Platform with touchscreen
  • Optional HeatNet Online Remote Monitoring
  • Natural gas/LP gas/dual fuel
  • Factory piped and wired
  • Vent/intake runs of up to 80 equivalent feet
  • Low NOx & CO2
  • Tru-Flow Advanced Air/Fuel Delivery System
  • Assembled boilers use 80% post-consumer recycled materials
  • 5x more wall thickness than stainless steel and aluminum
  • 90% AHRI-certified efficiency
  • Accepts 10:1 range of water flows (variable volume systems)
  • 100 psi maximum working pressure
  • 25-year heat exchanger warranty

KN26

KN Series Boiler

For More Information:
ATH-KN26-Boiler

Condensing, High Efficiency: 2,600,000 Btu

The KN26 continues the ATH KN-Series boilers’ tradition of excellence with its cast-iron heat exchanger and full-modulation capabilities. Producing 2,600,000 Btu within such a reduced footprint makes the KN26 a versatile condensing gas-fired boiler sized to meet the most demanding operations within the commercial boiler industry.

From single boiler applications to multiple boiler master/member networks controlled by HeatNet 3.0 software, the KN26 is built for the long haul. Developed for maximum efficiency, the KN26’s cast iron heat exchanger retains heat longer, allowing for shorter cycling and, most importantly, lower operating expenses.

Features and Benefits

  • 72” x 35” x 78” HWD footprint
  • 90% AHRI-certified efficiency
  • 25-year heat exchanger warranty
  • Optional 10:1 turndown
  • Accepts 10:1 range of water flows (variable volume systems)
  • 100 PSI maximum working pressure
  • 5x more wall thickness than stainless steel and aluminum
  • Plastic components are made from 40% post-consumer recycled materials
  • LEED-qualified
  • Tru-Flow Advanced Air/Fuel Delivery System
  • Assembled boilers use 80% post-consumer recycled materials
  • Factory piped and wired
  • Optional HeatNet Online Remote Monitoring
  • Natural gas/LP gas/dual fuel
  • Vent/intake runs of up to 80 equivalent feet
  • HeatNet Control Platform with touchscreen

KN30

KN Series Boiler

For More Information:
ATH-KN20-Boiler

Condensing, High Efficiency: 3,000,000 Btu

At 3,000,000 Btu, the KN30 is the largest boiler in the KN Series line. Without sacrificing reliability for size, the KN30 is designed to conquer the most significant, most challenging demands of the modern commercial boiler market, using a historical favorite, cast iron.

Condition-tolerant and heat-retentive, cast iron heat exchangers make the KN30 stronger and allow for short cycling, reducing boiler installation and operation costs over its lifetime. And when paired with full-modulation capabilities and HeatNet 3.0 boiler control software, the KN30’s high-efficiency condensing boiler technology continues to exceed industry standards and expectations.

Features and Benefits

  • 25-year heat exchanger warranty
  • Optional 10:1 turndown
  • Accepts 10:1 range of water flows (variable volume systems)
  • 72” x 35” x 86” HWD footprint
  • 5x more wall thickness than stainless steel and aluminum
  • 90% AHRI-certified efficiency
  • HeatNet Control Platform with touchscreen
  • Optional HeatNet Online Remote Monitoring
  • Low NOx & CO2
  • Natural gas/LP gas/dual fuel
  • LEED-qualified
  • Factory piped and wired
  • Vent/intake runs of up to 80 equivalent feet
  • Assembled boilers use 80% post-consumer recycled materials
  • Plastic components are made from 40% post-consumer recycled materials
  • 100 psi maximum working pressure
  • Tru-Flow Advanced Air/Fuel Delivery System

KN PLUS

KN Plus Series Ultra-High-Efficiency Boilers

For More Information:
ATH-KN20-Plus-Boiler

In a commercial market where efficiency is everything, the KN-Series stands out among the crowd as the only high efficiency, cast iron line of boilers to combine condensing gas-fired technology, with the strength, durability, and heat retention of cast iron construction. Durable, rugged and long-lasting, cast iron is the ideal material for condensing boiler systems that are built to last the long haul.

Facts:

  • Industry’s best 25-year heat exchanger warranty
  • KN-Series boilers have an installation base of over 26,000 units since their introduction
  • KN-Series boilers have not had one documented failure associated with corrosion
  • Cast iron is an acceptable material for use in condensing boiler applications by ASHRAE
  • Cast iron has been the material of choice in the boiler industry for over 150 years

Virtuoso₂

Turndown Controls

For More Information:
ATH-Virtuoso-O2-Monitoring

10:1 Turndown for KN-Series and KN-Series Plus

All ATH KN-Series boilers are available with the Virtuoso2 high turndown system. Working off the legendary Tru-Flow air/fuel coupling system, engineers at ATH have developed an air shutter-driven system expanding the KN’s turndown ratio to 10:1. The specially designed air shutter system is positioned between the venturi and the blower inlet. The air shutter opens and closes electronically at speeds dependent on the firing rate. The air shutter and blower protect against intake and flue pressure fluctuations by maintaining blower rpm. This provides complete combustion stability across the firing rate without sacrificing performance and reliability at any turndown ratio.

O2 Monitoring

Air density and temperature changes can affect boiler combustion. O2 sensors measure oxygen levels in the exhaust. The Virtuoso2 control platform incorporates a proven Bosch O2 sensor for real-time monitoring that can be instantly accessed by operators and technicians for instant adjustments for lower emissions and improved efficiencies.

Why is Cast Iron a Great Choice?

Cast iron is an ideal medium for condensing boiler applications due to its reliability and durability. Its corrosion-resistant properties make cast iron adverse to damage by acidic and basic pH levels. This casted metal is stronger than metals that are welded together. Set yourself apart on your next job with ATH KN-Series boilers.

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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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