Quick Product Details: KN Plus

Condensing Boilers

In today's commercial boiler market, efficiency, durability and the environment are everything. The KN-Series has stood the test of time and has outperformed the competition in all facets.

A staple in the condensing boiler market for over 15 years and over 26,000 installations the KN-Series uses the durability and heat retention capabilities of cast-iron heat exchangers with state-of-the-art air/fuel delivery systems and the HeatNet control platform to outpace the competition keeping KN at the head of the class.

Rugged and long lasting, cast-iron is the ideal material for condensing boiler systems. KNSeries boilers are built to last the long haul and backed by the industry's best heat exchanger warranty. All heat exchangers carry a 25-Year non-prorated warranty* covering materials and workmanship against failure due to condensate corrosion and thermal shock.
*See KN-Series written Warranty for specific requirements.


  • Industry's best 25-year heat exchanger warranty
  • KN-Series boilers have an installation base of over 26,000 units since its introduction.
  • KN-Series boilers have not had one documented failure associated with corrosion.
  • Cast-Iron boilers are 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.

KN-Series Plus Boiler Product Summary

KN Plus