Webasto Air Top Pro 25 Diesel 12V Mercedes Sprinter Kit with MultiControl

Quiet Diesel Air Heating for Mercedes Sprinter Camper Vans and Work Vehicles

Designed for 12V diesel Mercedes Sprinter applications, this vehicle-focused Webasto Air Top Pro 25 kit combines a quiet, continuously modulating air heater with Webasto MultiControl and essential installation components. It is well suited to camper van builds, work vans and overnight travel where steady cabin warmth matters. The diesel heater provides 2,400–7,000 BTU/h (0.7–2.0 kW) during continuous operation and up to 8,500 BTU/h (2.5 kW) in boost mode for up to six hours.

Application: Mercedes Sprinter diesel vehicles with a compatible 12V electrical system. Included control: Webasto MultiControl. RV use: RVIA standards compliant for RV and camper van applications; compliance of a finished conversion also depends on the complete installation.

Benefits & Everyday Use

• Steady cabin temperature: Stepless regulation adjusts heater output rather than repeatedly cycling at a fixed power level.
• Faster warm-up when needed: Up to 8,500 BTU/h (2.5 kW) in boost mode for up to six hours.
• Quieter overnight operation: Updated fan design and brushless EC drive help reduce operating noise in eco mode.
• Automatic altitude adjustment: Designed for operation up to approximately 18,045 ft (5,500 m), with maximum heating output available up to approximately 9,843 ft (3,000 m).
• MultiControl included: Dash-mounted screen, quick-start operation, heating/ventilation modes and programmable seven-day scheduling.
• Fuel pickup components: The kit includes a fuel standpipe and push-lock connector with adapter elbow and clamps for a suitably planned installation.
• Flexible installation: Compact heater designed for installation inside the vehicle or on the chassis where Webasto instructions permit.

Who Is This Heater Best For?

• Diesel Mercedes Sprinter camper van and Class B RV conversions that use a compatible 12V electrical system
• Adventure and overland Sprinter builds used in cold weather and at changing elevations
• Commercial Sprinter work vans where crews need cabin heat with the vehicle engine off
• Service and specialty Sprinter conversions where compact installation and scheduled heat are useful

Mercedes Sprinter Vehicle Fitment & Installation

This bundle is configured for diesel 12V Mercedes Sprinter applications, but fitment is not guaranteed for every model year or tank configuration. Confirm the vehicle fuel type, electrical system, fuel pickup, exhaust routing, available mounting space and current Webasto installation instructions before ordering or installing.

Kit Includes

• Air Top Pro 25 heater unit, 12V
• Webasto MultiControl controller
• Fuel pump DP42
• Air Top Pro 25 electrical wiring harness
• Flexible combustion-air intake tube with silencer, 22 mm × 0.5 m
• Fuel pump wiring harness extension, 6.56 ft (2 m)
• Fuel standpipe / pickup tube, 4.76 × 828 mm, 0.25 in NPT
• Stainless-steel exhaust hose with end cap, 22 mm × 3.28 ft (1 m)
• Exhaust silencer with mounting accessories
• Flexible warm-air ducting, 60 mm × 3.28 ft (1 m)
• Fuel tank push-lock connector with adapter elbow and clamps
• One warm-air outlet with fitting flange
• Installation hardware and accessories
• Mounting plate with sealing gasket

Important: The list above describes this Heatso vehicle-specific MultiControl bundle, not necessarily the contents of a standard Webasto factory heater kit. Install according to the applicable Webasto and vehicle-manufacturer instructions.

Technical Specifications

• Fuel: Diesel; manufacturer-specified paraffinic fuel (HVO/GTL).
• Rated voltage: 12V DC.
• Continuous heat output: 2,400–7,000 BTU/h (0.7–2.0 kW).
• Fuel consumption: 85–305 mL/h.
• Electrical power consumption: Maximum 21 W (heater specification).
• Boost mode: Up to 8,500 BTU/h (2.5 kW) for up to 6 hours.
• Ambient operating temperature: -40°F to 104°F (-40°C to 40°C).
• Altitude capability: Automatic adjustment; operation up to approximately 18,045 ft (5,500 m), with maximum heat output up to approximately 9,843 ft (3,000 m).
• Heater dimensions (L × W × H): 12.6 × 5.0 × 4.9 in (321 × 127 × 124 mm).
• Heater weight: 6.5 lb (2.95 kg); not the complete kit or shipping weight.
• RV compliance: RVIA standards compliant for RV and camper van applications.
• Mounting: Inside the vehicle or externally on the chassis, subject to Webasto installation requirements.
• Mechanical interface: Retains Air Top 2000 STC footplate and air inlet/outlet diameters; overall heater dimensions differ.
• Electrical interface: Heater-side 500 mm wiring harness with 8-pin connector and separate 1,000 mm dosing-pump cable, or the specified integrated harness arrangement.
• Communications: W-Bus, LIN and CI-Bus; Webasto identifies CAN J1939 implementation as forthcoming in the supplied materials.
• Conformity: ECE R10, ECE R122 and CE; designed with cybersecurity requirements according to ISO/SAE 21434.

Webasto Air Top Pro 25 vs. Air Top 2000 STC

The Air Top Pro 25 advances the earlier diesel Air Top 2000 STC with a wider low-output operating range, boost heating, automatic altitude adjustment and updated electronics. The comparison below refers to heater-level specifications, not the contents of these vehicle-specific installation bundles.

Replacing an Air Top 2000 STC

The Air Top Pro 25 retains the Air Top 2000 STC footplate and air inlet/outlet diameters, but the housing dimensions and electrical interface are different. Do not assume that an existing installation can be reused without changes. The wiring harness, controller connections, installation clearances and vehicle-specific components must be reviewed before a replacement.

FAQs

Will my Webasto heater still keep me warm at high altitudes?

Yes. The Air Top Pro 25 has automatic altitude adjustment for operation up to approximately 18,045 ft (5,500 m). Webasto specifies maximum heating output up to approximately 9,843 ft (3,000 m). Above that point, maximum heating output may be reduced as the heater adapts to thinner air. Actual warmth still depends on weather, insulation and the vehicle size.

Can I replace my Webasto Air Top 2000 STC with the new Air Top Pro 25 without modifying my setup?

Not necessarily. The Air Top Pro 25 preserves the older heater's footplate and air inlet/outlet diameters, but its overall dimensions and electrical connections differ. You may need an updated wiring harness, control connections and changes to the installation layout. Check the exact existing installation and Webasto guidance before treating it as a direct replacement.

Will this kit fit every Mercedes Sprinter?

No universal fitment is claimed. This bundle is intended for compatible diesel 12V Mercedes Sprinter vehicles. Verify model year, electrical system, tank/fuel connection, mounting location and installation clearances before ordering.

Does this kit include a Webasto MultiControl?

Yes. The product described here includes Webasto MultiControl, with a display, instant-start function and programmable seven-day heating schedule. It is not the separate Rheostat version.

Is the Webasto Air Top Pro 25 RVIA compliant?

Webasto describes the Air Top Pro 25 as compliant with RVIA standards for RV and camper van applications. A finished vehicle installation must also follow the applicable Webasto installation instructions and relevant vehicle requirements. RVIA compliance is not the same as claiming a separate RVIA product certification.

Can this heater be installed outside the vehicle?

Webasto states that the Air Top Pro 25 can be installed inside the vehicle or externally on the chassis. The selected location must meet applicable mounting, exhaust, combustion-air, fuel-line and other installation requirements.

What fuel and electrical system does this kit require?

This heater is specified for a 12V DC vehicle system and diesel fuel, including the HVO/GTL grades explicitly allowed by Webasto. Confirm the fuel grade and the vehicle electrical system against current Webasto guidance before installation.

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