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Harmonic Heating & Air Conditioning is here to take care of all your comfort system maintenance, repair and installation needs! Call us when you need comfort services!

Harmonic Heating & Air Conditioningstarstarstarstarstar5.0 / 5

216 Total Reviews /files//harmonic-logo-footer.png630-999-9008$10S187 Schoger Dr Suite #54, Naperville IL

K2 Condensing Stainless Steel Boiler

A value-priced' high efficiency condensing boiler that is simple enough to install quickly AND offers valuable extras not found on competitive models. U.S. Boiler Company has delivered. The K2 offers a comprehensive feature list' unequalled ease of setup' maintenance' and operation in a package that costs far less than you’d expect for the impressive value that’s built in. And best of all' it’s built and tested with pride in Lancaster' Pennsylvania by U.S. Boiler Company.

  • Reliable' proven stainless steel heat exchanger
  • Factory pre-set Sage2.2™ Control System' providing out-of-the-box high performance
  • Touch screen diagnostic display with plain-language guidance
  • Exclusive features for installer convenience and homeowner dependability
  • High altitude – zero or minimal de-ratings' reduces the costs of oversizing' field adjustable
  • High capacity pre-installed boiler loop circulator
  • Split-voltage junction box
  • Universal exhaust termination for polypropylene and PVC
  • Outdoor reset and sensor
MODELInput MBtuHOutput MBtuHAFUEDimensions
Water Content
K2-08080.0 74.0 94.0 29x17x16.2 0.00 149
K2-100100.0 92.0 93.0 29x17x16.2 0.00 158
K2-120120.0 111.0 94.0 29x17x16.2 0.00 162
K2-150150.0 141.0 95.0 29x17x20.2 0.00 188
K2-180180.0 167.0 94.0 29x17x20.2 0.00 188

Warranty Information

  • Heat Exchanger for 144 months - Limited 12 Year Warranty
  • All Parts for 36 months - With Prompt Online Registration
  • Limited Labor for 36 months - With Prompt Online Registration

Available Documents


We customize your comfort by making your home smarter, healthier and more efficient. Your peace of mind is as important to us as your comfort.

That's why every product us backed by warranties as robust and dependable as the products themselves.

Every piece of heating & cooling equipment is eligible for a 12-Year Parts Warranty, when you join the "Rock*Star Maintenance Program".

All other products are eligible for the 12-Year Parts Warranty.

Ask for details, terms, and conditions. All product warranties are registered by Harmonic within 30 days of purchase.

on all equipment repairs, indoor air quality & comfort items

Including humidifiers, air filters, air cleaners, thermostats and more! 12 year parts and labor warranty requires joining Rock*Star Maintenance Program. Ask for details, terms, and conditions.

The "Exclusive 12-year Parts & Labor Warranty" covers parts and labor cost from the time of purchase. "Exclusive 12-year Parts & Labor Warranty" requires annual maintenance to be performed by Harmonic Heating & Air Conditioning beginning immediately from the time of purchase. Maintenance must be performed annually during the initial 12-year coverage term in order to uphold warranty status. If annual maintenance is missed or not performed by Harmonic Heating & Air Conditioning, the "Exclusive 12-year Parts & Labor Warranty" becomes void immediately. Warranty coverage defaults to a 10 year part warranty and a 2 year labor warranty from the time of purchase. Warranty is registered to the purchaser and is not transferable.


when you purchase a Furnace or Air Conditioner from Harmonic!