Vitomax HW

High pressure hot water boiler

Output range: 0.35 to 20.0 MW

Output range: 0.35 to 20.0 MW
Flow temperature > 110 °C
High efficiency over 95.5 %
H2 ready 100 %

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High pressure hot water boiler

Output range: 0.35 to 20.0 MW

Flow temperatures

> 110 °C

High efficiency

With over 95.5 %

H2 ready

Operation with up to 100 % hydrogen

Wide range of fuel options

Such as hydrogen, natural gas, fuel oil, heavy fuel oil, biogases, bio-oils and many more

Safety temperatures

≤ 210 °C

Pressure levels

0.5 to 25 bar

Certification according to the Pressure Equipment Directive

For permissible flow temperatures > 110 °C

Corner stays arranged in pairs

Reduces stress in the boiler

Optimum flame tube geometries

For clean combustion

Longest possible inspection intervals and easy servicing

Due to sufficient inspection and access ports

For use in the manufacturing industry

Can be used in a wide range of industries

Vitomax HW high pressure hot water boilers from 0.35 to 20.0 MW for industry

Hydrogen up to 100 percent

In chemical operations such as the manufacture of chlorine and other industrial processes, most of the hydrogen gas is not used and is released into the atmosphere. Vitomax boilers, which can run on 100 percent hydrogen with an appropriate burner, offer a cost effective and efficient solution. At the same time a large amount of climate-damaging CO2 emissions is avoided.

Product features

The Vitomax HW high pressure hot water boilers meet all new statutory requirements for particularly clean combustion. The efficiency of these boilers with heat exchanger is over 95.5 percent, even at 100 percent load.

Regardless of the fuel used, the Vitomax HW delivers an output of up to 20.0 MW. It is specifically designed for the manufacturing industry as well as local and district heating networks where high flow temperatures and pressures are required.

Low stress, space saving design ensures good natural circulation and reliable heat transfer. No additional boiler pumps are required, making hydraulic connection significantly easier. The Vitomax HW can be operated very flexibly with light or heavy fuel oil, bio-oil or even (bio) natural gas.

No concrete is used for the optional innovative burner entry point in Vitomax boilers. This means it is water-cooled, and wear and maintenance-free, eliminating the need for replacement during the service life of the boiler. Water cooling guarantees a constant temperature around the burner head – the otherwise usual reflection from a refractory lining (which causes thermal NOx to form) does not occur.

The burner entry point and the rear flue gas reversing chamber of the Vitomax HW are water-cooled. This means the energy in the flue gases is used exclusively for hot water generation.

All Vitomax HW high pressure hot water boilers are suitable for the combustion of up to 100 % hydrogen when complying with our general conditions for the use of H2.

The spacing between the individual smoke tubes, as well as from the smoke tubes to the boiler casing and to the flame tube, comply with statutory requirements. The shearing force on the end face floors caused by different linear expansion in the smoke tubes and the flame tube is therefore extremely low. This design guarantees a long service life for the Vitomax HW.

Just like all other Vitomax boilers, the Vitomax HW is equipped with sufficient inspection and access ports for carrying out important checks inside the boiler. As a result, Vitomax high pressure hot water boilers achieve the longest possible inspection intervals. Easy to open boiler doors and a cleaning door at the end of the boiler also ensure that maintenance is simple and contribute to low running costs.

  • Hydrogen up to 100 %: comparable NOx values as in fuel oil/natural gas
  • Fuel oil (EL), NOx emissions (< 150 mg/m3 flue gas possible)
  • Heavy fuel oil, Mazut 100
  • Natural gas, NOx emissions (< 70 mg/m3 flue gas possible)
  • And many others, e.g. biogases/bio-oils or animal fats
  • Food processing industry
  • Fertiliser industry
  • Building material industry
  • Paper industry
  • Beverage industry
  • Chemical industry
  • Pharmaceutical industry
  • Hospitals
  • Refineries
  • Local and district heating networks

Product cross-section*

The product cross-section is only an example of what the Vitomax HS high pressure steam boiler may look like. Deviations are possible depending on the individual order.

Modularity – equipment level variations

  1. Burner entry point: 
    a) Lined (standard)
    b) Water-cooled – maintenance-free/wear-resistant (option)
  2. Boiler cover: 
    a) Without boiler cover / round insulation (standard)
    b) Walk-on boiler cover prepared for platform mounting (option)
  3. Modular operating platform (option – only in conjunction with walk-on boiler cover)
  4. Boiler support
    a) Cross plates (standard < 14t boiler weight) 
    b) Cross plates with longitudinal I-beams (option < 14t boiler weight / standard > 14t boiler weight 
    c) Full I-beam version (option)
  5. Flue gas collector with outlet to the rear:
    a) Round version (standard) 
     b) Rectangular version (option)    
  6.  Integral heat exchanger and flue gas collector: 
    a) Non-condensing heat exchanger (option) 
    b) Condensing heat exchanger (option) 
    c) Flue gas collector with round outlet
    Combination of non-condensing and condensing possible