Flextube Watertube

The “Flexible Water Tube” design provides for extremely fast, natural internal circulation, resulting in maximum heat transfer and operating efficiency. Dependency on external pumps is eliminated. The unique flexible bent tube design reduces all possible damage from thermal shock and related problems.

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PARKER – The Parker Boiler Co. was founded in 1946 and is a world-renowned manufacturer of industrial and commercial steam boilers from 1.5 H.P. to 150 H.P. with pressures to 250 PSI capable of delivering dry steam in under 10 minutes. We manufacture industrial and commercial direct-fired hot water boilers (available as gas, oil, propane, or combination-fired) ranging from 300,000 to 6,800,000 BTU, with operating temperatures to 400°F degrees and pressures to 300 PSI, Condensing Boilers 399,000 BTU to 5,433,000 BTU up to 180°F and 80 PSI. Our indirect-fired water heaters (available as gas or propane-fired) range from 300,000 to 3,000,000 BTU input, with operating temperatures to 190°F degrees and pressures to 150 PSI. We manufacture high temperature thermal liquid heaters (available as gas, oil, propane, or combination-fired) for process-heating up to 650°F degrees, ranging from 126,000 to 6,250,000 BTU input. We also are the makers of low NOx steam and hot water boilers and burner systems. Most models are UL or ETL listed. In addition to manufacturing our products, Parker Boiler is in the business of providing expertise and support to our customers.


PRECISION – The Precision FTH Series “Flex-Tube” boiler is a two drum system with multiple longitudinal pass separated by tangent water walls resulting in long turbulent gas travel without gas stratification. The furnace is fully water-cooled on all four sides and heat absorption does not exceed 60,000 BTU per cubic foot of furnace volume. Large downcomers are located outside the heat transfer zones to ensure positive natural circulation without relying on external circulation pumps. The boiler drums are independently supported by a structural steel frame to ensure that undue stress is not placed on the heat exchanger assembly.

Iroquois Flextube Boiler

Iroquois Flextube Boiler


  • 4,200 to 50,400 (100 to 1200 BoHP)
  • Compact Footprint
  • Patent Pending Design
  • ASME Section IV & Section I
  • Design Pressure Capability to 650 psig
  • Unique Optional Radiant Superheater Available
  • Multiple Pass Design
  • Easy Access to All Tubes for Maintenance
  • Optional Field Assembly Design Without Welding or Rolling

Request Flextube Watertube Specification & Information