• Boiler Front - Covers Off

    Boiler Front - Covers Off

  • Low Water Cut Off

    Low Water Cut Off

  • Top View

    Top View

  • Bottom View

    Bottom View

  • Back View

    Back View

  • Argus Vision Control with simple text display

    Argus Vision Control with simple text display

  • Heat Exchanger View

    Heat Exchanger View

  • Flue Collector

    Flue Collector

  • Removable Terminal Block

    Removable Terminal Block

Helix VLT Vertical Laser Tube, Wall Hung Modulating Condensing Boiler

Helix VLT

Innovative. Efficient. Dependable. Dunkirk.

The Dunkirk VLT features 95% AFUE. Plus:

  • Built-In Primary/Secondary Piping
  • Built-In Low Water Cut Off
  • 5:1 Turn Down Ratio
  • Approved for PVC, CPVC and Polypropylene venting
  • Patented Heat Exchanger, Patent No. 10,012,413 
  • Low Maintenance, Self-Cleaning
  • Designed in the US, for the US
  • 150 psi MAWP
  • ENERGY STAR® Certified


  • Efficiency: ENERGY STAR® Certified
  • Capacity: 50, 75, 100, 150, & 200 - All Dunkirk Helix VLT capacities are 95% efficient
  • Patented Heat Exchanger: Direct Vent, Patent No. 10,012,413 
  • Combustion: Sealed Combustion
  • Venting: Direct Vent
  • Boiler Type: Hot Water
  • Wall Mount: Bracket included.
  • Boiler Control Module: Automatic Line Voltage/Intermittent Direct Spark Ignition/Modulating with a 5:1 combustion turn down ratio. For multiple boiler applications - the control module can stage fire up to 16 boilers.
  • User Display Interface: Easy programming with text display. Outdoor Temperature Sensor included.
  • Heat Exchanger: High grade 316L/444 Stainless Steel Fin Coil with Flame Sight Glass.
  • Built-in Primary/Secondary Manifold Piping and Pump.
  • Combustion: Gas Valve with Premix Venturi and Blower, Durable Stainless Steel Mesh Modulating Burner with 5:1 turn down ratio, Direct Spark Igniter, Flame sensor and LP Conversion Kit included.
  • Electrical: Detachable Low Voltage Terminal Strip, High Voltage Junction Box and Transformer.
  • Other
    • Factory installed probe-type Low Water Cut Off with test feature
    • 30 PSI Safety Relief Valve
    • Boiler Drain Valve and Condensate Drain with built in trap.


  • Central Heating Pump available for 50 to 200 MBH (Taco 007 or Grundfos UP15-42F).
  • Concentric Vent Kit (2" and 3").
  • Floor Stand Kit.
  • System Sensor (For Multiple Boiler Applications).

Documents / Resources

Current Documents
Archived Documents


User Manual

Installation & Operation Manual

Parts Lists


Engineering Documents / Resources


Product Testimonials

  • Good design. Clean unit. No wasted space in cabinet. Appreciate the "English" control panel (vs. obscure coding). Very quiet and compact.

    Unit looks to be well built. I am an engineer/operator, and appreciate the design and assembly of the unit.

    John Steiner
    Golden, CO
  • Very nice and clean installation, doesn't require much room.

    User friendly.

    Brad King
    Spokane, WA
  • Yes I would recommend this product.  Great value and easy to install.

    Antonio Pereira
    Yonkers, NY