Eberspacher Hydronic S3 D5
The Eberspächer Hydronic S3 D5 is a premium 5kW diesel liquid heater, representing the pinnacle of compact hydronic heating technology.[…]
Read moreFor boaters who require a “domestic-style” heating experience, a hydronic diesel system is the premier choice for on-board climate control. These units, often referred to as “wet heaters,” circulate a heated water-glycol mixture through a circuit of radiators or matrix heaters, while simultaneously providing a consistent supply of domestic hot water via a calorifier. This method of marine climate control is exceptionally quiet and offers superior heat retention compared to air-based systems, making it ideal for larger vessels and year-round live-aboards.
Designing a water-based heating circuit requires a high level of technical precision to ensure the system operates without “cycling” or overheating. Our engineering approach focuses on hydraulic balancing and component longevity.
We provide professional installation and commissioning for the industry’s most reliable hydronic manufacturers:

Webasto: The Thermo Pro 90 and Thermo Top series are renowned for their quiet operation and compact design.

Autoterm: The Flow 5 (Hydronic) is a rugged, service-friendly unit that offers exceptional value for high-use vessels.

Eberspächer: The Hydronic series offers high-performance German engineering with sophisticated digital control options.
See all our diesel water heaters in no particular order below. This is a collection of compatible models across our range; for more detailed listings and technical specifications, please follow the main menu to our manufacturer-specific pages.
To ensure your vessel remains compliant with Canal & River Trust (CRT) licensing, all diesel water heaters must be installed according to Boat Safety Scheme (BSS) mandates. This includes specific requirements for the installation of ISO 7840-compliant fuel hoses, fire-protected copper fuel lines, and correctly routed wet exhausts.
As OFTEC registered technicians, we ensure that every hydronic system meets the relevant standards. Our commissioning process includes a full analysis to verify that the heater is burning cleanly, preventing carbon buildup and protecting your manufacturer’s warranty.

The Eberspächer Hydronic S3 D5 is a premium 5kW diesel liquid heater, representing the pinnacle of compact hydronic heating technology.[…]
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The Autoterm Flow 5 (formerly the Binar 5S) is a powerful and compact 5kW diesel liquid heater designed to provide[…]
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The Autoterm Flow 14TC-Mini is a heavy-duty 14kW diesel liquid heater designed for larger vessels, widebeams, and barges. As the[…]
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The Webasto Thermo Top Evo is a powerful and compact diesel liquid heater (boiler) specifically designed for marine applications. Delivering[…]
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The Webasto Thermo Pro 90 is a powerful and robust diesel water heater (hydronic) designed for larger marine vessels, such[…]
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