Models: W750, W1000, W1500, W1700, W2000

When it comes to small size but big output, the P-K THERMIFIC VELOX® Direct Fired Water Heater is hard to beat — Even the largest model can be moved through a 30″ doorway!

Its state-of-the-art vertical design utilizes a radial-fired, fan-assisted burner and heat exchanger, enabling the P-K THERMIFIC VELOX® W Series Direct Water Heater to operate at a CSA certified thermal efficiency of 85% as a Category I non-positive, non-condensing appliance.

Whether installed as an individual unit or paired with a storage package, the P-K THERMIFIC VELOX® W Series adapts to fit the needs of the application. There are only five connections in this easy installation, and multiple units can be installed together in small areas to meet virtually any heating load– A unit ideal for retrofitting.

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General Documents

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NURO® Touch-Screen Control System

Turndown energy usage

Thermific VELOX® water heaters are equipped with the most intuitive interface in the industry, the NURO® Touch-Screen Control. Designed to maximize efficiency, the NURO® Control System monitors and modulates the combustion and ignition of the boiler to maintain the desired outlet temperature.


  • Optional storage tank can complete the package; contact us for more information
  • Compact/modular design allows multiple units to be installed in tandem
  • Vertical burner/heat exchanger design
  • Unique integral finned copper water tubes
  • High heat transfer ratios
  • Lo-Hi-Lo operating controls on some models
  • Propane option
  • Sealed combustion option
  • Operates quietly, below OSHA standards
  • CSA certified and ASME approved
  • 5 Year Warranty


  • One of the highest achievable thermal efficiency levels for non-condensing, gas-fired boiler
  • Does not produce highly corrosive condensate in either the heat exchanger or vent system when operated at recommended temperatures
  • Needs only five connections to install
  • Low installation and maintenance costs
  • Certified for installation on combustible floors
  • Compact to clear a 30″ doorway
  • Sealed combustion eliminates large air louvers and permits boiler installation in a negative pressure environment or adjacent to refrigerants
  • Burner can be quickly and easily removed from the exchanger for cleaning or inspection
  • High heat transfer ratio and fast response to load requirements
  • Easy access, ideal for retrofits in inaccessible locations
  • Fire tested before shipment

Contact us to learn more about the Patterson-Kelley difference.

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