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Core Features & Benefits
Gasoline Air and Water Heating kit for RVs and Camper Vans
The Espar Hydronic S3 B5E CS is a compact 12V gasoline water heater kit for RVs, camper vans and motorhomes. It uses gasoline from the vehicle’s fuel tank to heat a closed coolant circuit, delivering up to 17,000 BTU/h (5 kW) for cabin heating and non-potable hot water.
The included Kalori EVO 1 blower heater transfers heat from the coolant into the living space. A separate 24-plate heat exchanger with a mixing valve can transfer heat to a non-potable water circuit for applications such as washing or showering, subject to local requirements.
Includes a Kalori EVO 1 blower heater for cabin heating
Supports non-potable water heating through a separate plate heat exchanger
Can operate independently or connect to the engine coolant circuit
EasyStart Pro provides heater control, timers and diagnostics
Supports operation up to 9,900 ft (3,000 m) with high-altitude mode
Compact heater can be installed outside the living area
Fully customizable for different RV heating requirements
Fully Customizable Hydronic Heating
The B5E provides a flexible foundation for a custom RV hydronic system. Additional water-to-air heat exchangers, hydronic radiators, floor-heating loops and separate heating zones can be added when correctly sized and installed.
The system may also be configured for engine preheating or for using engine heat while driving. Additional pumps, valves, manifolds, thermostats and control components may be required.
All heating elements share the Hydronic’s maximum 17,000 BTU/h (5 kW) output. Adding more heating zones improves heat distribution but does not increase the total available heating power.
How the System Works
The B5E burns gasoline to heat a water-glycol coolant mixture. An external circulation pump moves the hot coolant through the Kalori cabin heater, plate heat exchanger and any optional heating elements.
The primary coolant and secondary water circuits remain separate and do not mix. The supplied 5-liter tank is an expansion tank for the closed coolant circuit—not a hot-water storage tank.
Non-Potable Water Notice: The included plate heat exchanger is intended for non-potable water applications. Water heated through this component must not be used for drinking, cooking or food preparation. Confirm applicable requirements before using the system for washing or showering. A certified potable-water heat exchanger and compatible plumbing components are required for potable hot water.
Technical Specifications
Fuel: Gasoline / petrol
Voltage: 12V
Heat output: 6,140 - 17,000 BTU/h (1.8 - 5.0 kW)
Maximum output: approximately 17,000 BTU/h
Maximum fuel consumption: 0.67 l/h (0.18 gal/h)
Hydronic electrical consumption: approximately 7–32 W
Coolant pump consumption: approximately 17 W
Kalori EVO 1 blower consumption: up to 70 W
Maximum operating altitude: 3,000 m (9,900 ft)
Heater dimensions: 215 × 91 × 144 mm
Heater weight: approximately 2 kg
Kalori EVO 1 heating capacity: approximately 4.3 kW
