Webasto Thermo E+ 320 Diesel Heater Kit with Enclosure Box

Diesel coolant heater for reliable cold starts

Improve cold-weather readiness and reduce engine strain with a high-output diesel coolant heater built for demanding land-based equipment. This Webasto Thermo E+ 320 heater kit delivers 109,100 BTU/h (32 kW) of coolant heating power and is available in 12V or 24V enclosure box configurations.

Benefits & Use Cases

Designed for large diesel engines and heavy-duty applications, this coolant heater helps preheat the engine for easier starts in freezing conditions while supporting supplemental interior heat when the vehicle is running.

The Thermo E+ 320 is especially useful for off-highway equipment, work trucks, specialty vehicles, and cold-climate fleets where dependable heat helps reduce cold-start wear, lower white smoke, and improve visibility through faster defrosting.

• Preheats large diesel engines for easier cold-weather starts
• Helps reduce cold-start wear and white smoke emissions
• Supports supplemental vehicle interior heat while the engine is running
• Provides strong heat output for demanding off-highway and specialty vehicle use

Technical Specifications

• Fuel Type: Diesel, Arctic diesel, and kerosene
• Voltage: 12V or 24V configuration
• Max Heat Output: 109,100 BTU/h (32 kW)
• Fuel Consumption: 0.85 gal/h (3.22 liters/h)
• Power Consumption: 110 W without water pump
• Max Altitude: No adjustment required up to 3,300 ft (1,000 m); brief operation up to 6,600 ft (2,000 m)
• Warranty: 2 Years
• Dimensions (Heater body only): 593 × 249 × 224 mm (23.4 × 9.8 × 8.8 in)
• Weight: Heater body 38.1 lb (19 kg); heater with enclosure box 78.1 lb (34 kg)
• Coolant Connections: 1.5 in (38 mm) I.D.
• Fuel Lines: 0.25 in (6 mm) I.D.

Part numbers:

• 12V enclosure box kit: 5013850B
• 24V enclosure box kit: 5013851B
• 12V Heater only: 11149427A
• 24V Heater only: 11149428A
• Alternative formats: 5013851; 5013850

Browse Webasto Manuals & Technical Documentation

Compatibility

• Large diesel engines requiring coolant preheating in cold weather
• Off-highway equipment and heavy-duty land-based machinery
• Work trucks, specialty vehicles, and commercial vehicle coolant systems
• Engine preheat and supplemental heat circuits using compatible coolant plumbing
• Not approved for marine use

Kit Includes

• Thermo E+ 320 Heater
• Wiring Harness
• Electrical Connector Kit
• Flexible Stainless Steel Exhaust Tubing
• Coolant Pump
• Power/Switch Harness
• Toggle Switch
• Standpipe
• Fuel Filter

FAQs

What is the Webasto Thermo E+ 320 used for?
It is a high-output diesel coolant heater for large diesel engines, off-highway equipment, and specialty vehicles. It preheats coolant to support easier cold starts and can help provide supplemental heat through the vehicle heating circuit.

Is this listing for the 12V or 24V Thermo E+ 320?
This listing includes both options. Choose the 12V enclosure box kit PN 5013850B or the 24V enclosure box kit PN 5013851B depending on your vehicle electrical system.

How much heat does the Thermo E+ 320 produce?
The heater produces 109,100 BTU/h (32 kW), making it suitable for large coolant systems and demanding cold-weather applications.

Can the Thermo E+ 320 be used at altitude?
No adjustment is required up to 3,300 ft (1,000 m). Brief operation is allowed up to 6,600 ft (2,000 m), while extended use above 3,300 ft may require adjustment at the operating altitude.

Does this heater need regular maintenance?
Yes. The installation manual recommends annual maintenance before the heating season, including checks of the enclosure area, electrical system, exhaust system, fuel system, and burner system.