Industrial FLX Premix Watertube Boiler — Steam and Hot Water

R.F. MacDonald Co. services and sells boilers, pumps, composites and accessories for commercial and industrial applications.

CB Boiler Model FLX Premix

CB Model FLX Premix

FLX Premix BoilerThe Model FLXPM Flextube boiler achieves best-in-class combustion performance with low emissions. Premix burner technology enables the boiler to attain <20 ppm NOx without FGR and <10 CO as standard on natural gas. The modulating burner control automatically adjusts the air/gas mixture for maximum efficiency and optimum turndown.

• Steam and hot water
• 75 to 250 HP
• Available to <9 ppm NOx, ultra-low CO
• Natural gas or propane fuel
• Premix burner technology
• Up to 5:1 turndown

Product Overview

The FLXPM integrates a servo-driven, fuel-input control valve with air-input control via a variable-frequency-driven fan for precise fuel/air ratio control.

Its compact design makes it easy to fit several units into a boiler room or into a larger hydronic system of condensing or non-condensing boilers. This multi-unit solution helps to divide the load more efficiently in a hydronic or in a steam process.

Because there is no requirement for FGR piping from the stack to the burner, it is easy to incorporate the FLXPM into a new or existing boiler system.


• Small footprint
• Ultra quiet
• Design protects against thermal stresses
• Hinged burner door for easy access
• 25-year warranty


• Lower Fuel Cost
• Lower Emissions


• Process Steam
• Industrial Process
• Building Heat
• Sterilization
• Hospital and Healthcare