Maddock is excited to announce the addition of the KN Series boilers from Mestek Boiler Group to our commercial heating lineup.
As the only American-made, cast-iron condensing boilers on the market, the KN Series blends traditional strength with modern performance. This makes the KN Series ideal for retrofits, replacements and new construction alike.
A Return to Cast-Iron Durability
Cast-iron sectional boilers have long been a gold standard in heating due to their durability, thermal mass, and long service life. While many modern high-efficiency boilers rely on thin stainless steel or copper heat exchangers, the KN Series goes back to a time-tested approach – with a modern twist.
Each KN boiler features a modular, cast-iron sectional design that is built to last, with thicker walls and unmatched heat retention. These boilers are engineered and manufactured at the Mestek foundry in Boyertown, Pennsylvania, carrying on a legacy of American craftsmanship.
For facilities that prioritize domestic sourcing, the KN Series offers a reliable, US-made solution that supports local industry and ensures dependable lead times.
High-Efficiency Performance, Condensing or Not
The KN Series stands out for more than its durability. It’s also the first and only cast-iron boiler that can operate in both condensing and non-condensing modes. When conditions allow for lower return water temperatures, the boiler operates in condensing mode with thermal efficiencies exceeding 90%. But unlike most high-efficiency units, the KN Series can also handle higher temperature returns without corrosion, making it far more forgiving in real-world conditions.
This dual-mode capability gives building operators flexibility: maximize energy savings with condensing operation, while maintaining peace of mind with a boiler tough enough to handle challenging system water or fluctuating loads.
Built for Retrofit Applications
One of the key advantages of the KN Series is its seamless integration into existing buildings. Thanks to its sectional construction, each boiler can be taken apart and transported in pieces via standard doorways or elevators—perfect for retrofits where access is limited. Once in place, the sections are reassembled on-site, eliminating any need for structural modifications.
For contractors and engineers working on updates to older facilities, this can translate to faster installations, lower costs, and fewer headaches. Whether you’re replacing a legacy boiler or adding capacity, the KN Series offers a practical and scalable solution.
Smarter Controls, Streamlined Operation
Every KN boiler is equipped with HeatNet 3.0, an advanced control system with a full-color touchscreen, real-time monitoring, and built-in boiler sequencing. Up to 16 units can be networked together with no external controller required, providing seamless lead-lag and cascade functionality right out of the box.
The platform also supports remote monitoring, web-based diagnostics, and integration with building management systems, which gives facility managers better visibility and control over system performance.
Flexible Sizes & Applications
Available in models ranging from approximately 200,000 to 3 million BTU/hour, the KN Series accommodates a broad spectrum of commercial applications, including schools, offices, hospitals, and government buildings. Whether used as standalone units or in multi-boiler configurations, these boilers are compact, quiet and designed for long-term service.
And with its cast-iron construction rated up to 100 psi, the KN Series is robust enough for demanding system designs while still being nimble enough for tighter footprints.
American Made, Maddock Supported
At a time when reliability, supply chain confidence, and product longevity matter more than ever, the KN Series delivers. It’s built in America using domestic materials, engineered for real-world conditions, and supported by one of the most advanced control systems available.
Now part of Maddock’s boiler offering, the KN Series rounds out our lineup, giving us the most complete range of modular commercial boilers in the Chicagoland area.
Are you unsure which boiler is best suited for your facility? Maddock’s team of engineers and mechanical experts is here to help. Whether you’re planning a retrofit or a new installation, we can assess your heating system, recommend the right equipment, and support you from selection through installation.
Contact us today to learn more about the KN Series and how it can enhance your building’s efficiency, reliability, and long-term performance.
