FTH FLEXTUBE GAS/OIL FIRED
This unit with its flex tube forced draft design allows for high fuel to output efficiency in a smaller, easy to maintain design that uses natural heat convection to ensure consistent internal heat flow and complete internal water circulation. Known for its smaller size, the system can handle up to 150 degrees F. temperature differences from the supply and return and offers almost instant hot water. The system can be designed to communicate with any building management system. Other options such as construction under ASME Section I/VII for high temperature hot water usage are also available.
The lower return water vessel is connected to the upper supply vessel via carbon steel tubes which form a 5 pass heat transfer space which provides around 5 sq. ft. of heating surface per BHP. To ensure positive water circulation in the heating tubes, a single down-comer attaches the lower and upper vessels on the exterior of the boiler cabinet to maximize natural internal convention.
These units can be supplied to fit in areas where access is minimal and then can be reassembled without on-site code welding. Units are available in NOx designs as low as sub-9ppm and include a 25 year warranty against thermal shock.