Superheated Water Boiler

Advantages of Pressurized Hot Water Boilers

• Simple and efficient operation with cost-effective installation
• Easy maintenance and inspection requirements due to relatively low operating pressure
• High heat transfer efficiency enabled by large corrugated combustion surfaces
• Fast response to system load demands thanks to low water volume and high circulation rates
• Excellent accessibility to gas and water sides via front doors, rear explosion door, manholes, and multiple handholes
• Custom-designed solutions tailored to specific customer and process requirements
• Decades of engineering and manufacturing experience in industrial and commercial boiler technologies
• Precise temperature control ensuring stable and safe process conditions
• User-friendly interface supported by TSB ENERGY control systems
• High process reliability with remote monitoring and control capabilities
• Strict quality control procedures applied throughout all production stages
• Long, trouble-free service life ensured by balanced thermal expansion design and approved automatic welding methods
• Up to 1% additional combustion efficiency achieved with aluminum turbulators
• Low electrical consumption through the use of high-efficiency electric motors
• Environmentally friendly operation with low NOx emission levels
• Contribution to CO₂ emission reduction through hydrogen-ready combustion capability
• Customer-specific software and automation adaptations developed by our expert engineering team
• Optional PLC-based control architecture supporting Modbus and Profibus communication protocols
• Easy and safe integration into all types of industrial processes

Operating Principle of Pressurized Hot Water Boilers

Pressurized hot water boilers are structurally similar to steam boilers; however, during operation the boiler shell is completely filled with water and operates on a closed-loop circulation principle.

The burner installed within the boiler generates flame and flue gases in the combustion chamber. The released thermal energy is transferred to the water through large heat transfer surfaces. The heated pressurized water is circulated to the process via pumps and piping systems. After releasing its heat to the process equipment, the water returns to the boiler through the closed circuit to be reheated.

For safe and long-term operation, proper water treatment is essential. Maintaining controlled pH levels in the closed-loop system significantly minimizes corrosion risks and extends system lifetime.

Design: TSB ENERGY pressurized hot water boilers are designed and manufactured in accordance with TS EN 12953 as well as relevant EN, DIN, TRD, and Lloyd’s regulations.
For European Union projects, systems are certified in compliance with the PED 2014/68/EU Directive. Upon request, designs can also be executed according to ASME Section VIII Division 1.

All electrical components are UL-approved, and wiring as well as control panels are manufactured in full compliance with applicable National Electrical Code (NEC) requirements.

Combustion Chamber: The three-pass combustion chamber design developed for TSB ENERGY pressurized hot water boilers is the result of university-supported R&D programs. The large combustion volume and balanced flue gas flow distribution across the second and third passes ensure high heat transfer efficiency and stable combustion conditions.

This optimized configuration enables complete fuel combustion while maximizing overall system efficiency. Thanks to the optimized combustion geometry, low NOx and CO emission levels are achieved, fully compliant with applicable CE and European Union regulations. Performance is verified through independent testing conducted by EU-authorized laboratories.

Turbulators: Stainless steel and Corten steel turbulators installed inside the smoke tubes create controlled turbulence in the flue gas flow. This increases gas velocity and residence time within the tubes, significantly enhancing the heat transfer coefficient and directly contributing to higher boiler efficiency.

Door System: The front door of TSB ENERGY pressurized hot water boilers is designed to open in both directions. Independent adjustment mechanisms at all four corners ensure uniform sealing pressure, providing full tightness under all operating conditions.

Front Door Insulation: Front door insulation is achieved using high-temperature-resistant refractory concrete. This structure minimizes heat losses in the door area. Flexible, thick fiberglass-reinforced gaskets ensure complete gas tightness, delivering safe and efficient operation.

TSB ENERGY pressurized hot water boilers are designed not only to deliver value at purchase, but to generate savings throughout their entire operating life.

Ease of Operation and Maintenance: User-friendly control systems and easy access to service components significantly simplify operation and maintenance procedures. One-button start-up functionality allows the system to perform self-checks and safely shut down in case of abnormal conditions.

The control panel provides operating-hour-based warnings and summarized maintenance notifications, ensuring safe and intuitive operation for boiler operators.

TSB ENERGY pressurized hot water boilers feature advanced instrumentation and automation systems fully compliant with CE regulations and EN 12953 standards. The system can operate safely without continuous operator presence and automatically shuts down and locks in case predefined safety limits are exceeded.

Safety: Safety and full compliance with international standards are the top priorities in the design of TSB ENERGY pressurized hot water boilers. Systems are equipped with overpressure protection, flue gas temperature monitoring, and pressurized water temperature supervision. In case of any limit exceedance, the boiler is automatically shut down to ensure maximum operational safety.

Materials: Boiler shells and tube plates are manufactured from P355GH boiler steel in accordance with EN 10028-2. Nozzles and connection piping are produced using P235GH or P265GH boiler tubes compliant with EN 10216-2. This material selection guarantees safe and long-lasting operation under high temperature and pressure conditions.

Efficiency: As a result of extensive R&D activities, the smoke tube geometry and combustion chamber design of TSB ENERGY pressurized hot water boilers have been optimized. Improved flue gas flow characteristics enhance heat transfer efficiency and combustion performance.

These optimizations result in up to 4% fuel savings compared to standard designs, while simultaneously achieving lower NOx emission levels.

Hydrogen Compatibility: Hydrogen gas released during chlorine production and similar chemical processes is often vented to the atmosphere without being utilized. This hydrogen, which is difficult to store and transport, can be safely and efficiently converted into energy using suitable burner technologies in TSB ENERGY pressurized hot water boilers.

Successful applications include chlor-alkali plants, chemical and petrochemical facilities, electrolysis processes, and industrial production lines generating hydrogen as a by-product. This approach reduces waste gas emissions while providing a sustainable heat source for industrial processes.

Environmentally Friendly Design: TSB ENERGY pressurized hot water boilers are developed with a strong focus on minimizing environmental impact. Optimized clean combustion allows NOx emissions to be maintained below 70 mg/Nm³ for gas-fired boilers and below 150 mg/Nm³ for liquid-fuel-fired boilers.

All industrial liquid- and gas-fired TSB ENERGY boilers can be configured to operate with up to 100% hydrogen, using appropriate burner systems. Thanks to boiler geometry optimized for high-velocity flame and flue gas flow, low NOx levels are maintained even during hydrogen combustion. Additionally, reduced fossil fuel usage leads to significant CO₂ emission reductions.

Customization: We understand that every production line and industrial process has unique requirements. Therefore, our pressurized hot water boilers—proven in hundreds of applications—are customized based on detailed process analysis to deliver the most efficient and reliable configuration for your operation.

Designing, manufacturing, and successfully commissioning pressurized hot water boilers requires advanced engineering expertise and experienced technical personnel. With TSB ENERGY, you acquire not only a boiler, but decades of engineering know-how and industry experience. For further information, feel free to request personalized expert consultation.

Options and Integrated Solutions

For each pressurized hot water boiler, TSB ENERGY offers the following optional systems and integrated solutions:

• Advanced automation and control systems
• Water treatment, conditioning, and continuous analysis solutions
• Heat recovery systems
• Process piping and chimney systems
• High-efficiency, low-emission combustion technologies
• Standard micro-modulating burner applications
• Service-friendly, easy-maintenance design
• Robust mechanical construction for extended service life
• Condensing economizer systems
• Combustion air preheaters
• Dual-fuel and mixed-fuel firing options
• O₂ and CO trim control systems
• Fully integrated, turnkey pressurized hot water solutions

What Is a Pressurized Hot Water Boiler?

A pressurized hot water boiler is a pressure vessel system in which water is circulated in liquid phase above its boiling point within a closed-loop circuit. Heat generated in the combustion chamber is transferred to the water via flame and smoke tubes, providing a safe and efficient heat source for high-temperature industrial processes.

When Is a Pressurized Hot Water Boiler Used?

Pressurized hot water boilers are preferred for medium- and high-temperature applications where water must be maintained above its boiling point without phase change. They offer an economical and safe heating solution for processes requiring continuous and precisely controlled temperatures above 100 °C, without the need for steam.

In industrial applications, pressurized hot water boilers are typically used for process temperatures ranging from 90–180 °C. For higher temperature requirements, steam or thermal fluid systems are preferred. Thanks to their closed-loop operation, precise temperature control, and low operating costs, pressurized hot water boilers are widely used in chemical, food, energy, construction materials, and central heating systems.

Ideal Selection of a Pressurized Hot Water Boiler

• Modern three-pass boiler designs with reduced footprint, low water volume, and minimized heat losses should be preferred for maximum efficiency.
• Motorized three- or four-way valves should be used to automatically regulate supply water temperature based on outdoor conditions.
• Modulating burners should be selected to match heat output precisely to system demand.
• Where applicable, high-efficiency condensing boiler solutions recommended by TSB ENERGY should be considered.
• Burner capacity must be properly matched to boiler output to minimize start-stop cycles.
• Facilities with highly variable daily heat demand should implement redundant boiler systems connected to a common header.
• Boiler room layout must comply with operating conditions, local regulations, and boiler classification requirements.

Applications

• Greenhouses
• Farms and livestock facilities
• Chemical and process industries
• Food industry (juice, pasta, dairy production, large bakeries, sterilization processes)
• Fertilizer industry
• Construction materials industry
• Paper industry
• Wood processing and forming facilities
• Central hot water heating systems