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(Pre-Order) Webasto Air Top Pro 25 Diesel Heater Kit, 12V, Rheostat Control

The Webasto Air Top Pro 25 is the new diesel air heater from Webasto. It makes up to 8,500 BTU/h (2.5 kW) in boost mode, runs quietly at low output, and adjusts for altitude on its own. This sleeper kit includes the heater, a simple dial controller, and the parts you need to install it. Pre-order sale: 15% off now through November 12th. Pre-orders are expected to ship between November 20th and December 1st.
$ 1,593.75 $ 1,875.00

  • Brand
  • Fuel
  • Thermostat Type
  • Max Heat Output
Brand: Webasto
Fuel: Diesel
Thermostat Type: Analog
Max Heat Output: 2.5kW

This is the simplest way to get the new Air Top Pro 25 in a diesel van, RV, or truck. A rotary dial sets the heat, and the kit has the parts to install it. It is the lowest-priced Air Top Pro 25 diesel kit we offer.

The Air Top Pro 25 is Webasto's new air heater for trucks, vans, RVs, buses, and work vehicles. It replaces the Air Top 2000 STC. It gives you more heat and more control in a body that is about the same size.

This is the diesel sleeper kit with the rheostat dial controller. It replaces Webasto's Air Top 2000 STC 12V Diesel Truck Sleeper Kit (5012550A). It is a good fit for truck sleeper cabs, vans, and RVs that run on diesel.

It has the widest heat range in its class. In normal use it runs from 2,400 BTU/h (0.7 kW) up to 7,000 BTU/h (2.0 kW). Boost mode gives you 8,500 BTU/h (2.5 kW) and holds it for up to 6 hours. The heater changes its power in small steps to hold the temperature you set. A low minimum output means fewer restarts. That is easier on your battery and quieter at night.

How it compares to the Air Top 2000 STC

FeatureAir Top Pro 25Air Top 2000 STC
Heat range (diesel)2,400 to 7,000 BTU/h (0.7 to 2.0 kW)3,100 to 7,000 BTU/h (0.9 to 2.0 kW)
Boost mode8,500 BTU/h (2.5 kW) for up to 6 hoursNot available
Altitude adjustmentAutomaticManual
Fan driveBrushless EC motorDC motor
Size (L x W x H)12.6 x 5 x 4.9 in (321 x 127 x 124 mm)12.25 x 4.78 x 4.85 in (311 x 120 x 121 mm)
Footplate and air inlet/outletSame as the 2000 STCStandard

The controller

This kit comes with the rheostat dial controller. It is a digital rotary selector with an LED status display. Turn it to set the heat level. The heater adjusts its power smoothly to match. It is compact and mounts in the dash. Mounting it needs a hole drilled in the dash panel.

Technical specifications

SpecificationValue
FuelDiesel. Also runs on paraffinic fuel (HVO/GTL).
Voltage12 V
Heat output, control range2,400 to 7,000 BTU/h (0.7 to 2.0 kW)
Heat output, boost8,500 BTU/h (2.5 kW), up to 6 hours
Fuel consumption2.9 to 10.3 fl oz/h (85 to 305 ml/h). About 12 to 44 hours per gallon.
Electrical power consumption21 W max
Operating temperature-40 to 104 F (-40 to 40 C)
AltitudeOperates up to about 18,000 ft (5,500 m). Full heat output up to about 9,800 ft (3,000 m).
Size (L x W x H)12.6 x 5 x 4.9 in (321 x 127 x 124 mm)
Weight6.5 lb (2.95 kg)
FanBrushless EC motor
Mechanical interfaceSame footplate and air inlet/outlet as the Air Top 2000 STC
Electrical interface19.7 in (500 mm) wiring harness with 8-pin connector, plus 39.4 in (1,000 mm) dosing pump cable
CommunicationW-Bus, LIN, CI-Bus. Webasto lists CAN J1939 as "available soon."
Approvals and standardsECE R10, ECE R122, CE. Cyber security to ISO/SAE 21434. Functional safety to ISO 26262.

Fuel hours per gallon are calculated from Webasto's fuel consumption figures.

What is in the kit

  • Air Top Pro 25 diesel heater, 12V
  • Rheostat dial controller
  • Fuel pump
  • Base seal
  • Heater wire harness
  • Fuel pump wire harness
  • Fuel line
  • Heavy-duty fuel tank standpipe
  • Flexible stainless steel exhaust tubing
  • Combustion air tubing
  • Flexible cabin air ducting
  • Air louvers

Installation notes

  • The heater mounts inside the vehicle or outside on the chassis.
  • It uses the same mounting footplate and air inlet and outlet sizes as the Air Top 2000 STC. The wiring and controller are new, so use the harness and controller in this kit.
  • The wiring is plug and play, with a 19.7 in (500 mm) heater harness and a separate 39.4 in (1,000 mm) dosing pump cable.
  • Installation needs a hole for the exhaust, a hole for the combustion air, a tap into your fuel tank, and a hole in the dash for the controller.
  • The heater draws fuel from your vehicle's tank. You do not carry separate fuel.
  • Professional installation is available at any Momentum Upfitters location. Submit an installation inquiry. See the pricing below.

Professional installation

Professional installation is available at any Momentum Upfitters location. We have shops in Salt Lake City, Utah and Fort Collins, Colorado. Installation generally costs:

VehicleInstallation price
Vans with an aux fuel port$999
Most other vehicles$1,299

To have this heater installed, submit an inquiry on our heater installation page. We will confirm pricing for your vehicle.

Important information

  • Match the heater to your fuel. This kit is for diesel vehicles. If your vehicle runs on gasoline, choose a gasoline kit.
  • Boost mode gives 8,500 BTU/h (2.5 kW) for up to 6 hours at a time.
  • Altitude. Full heat output is available up to about 9,800 ft (3,000 m). Above that, the heater adjusts automatically and keeps running up to about 18,000 ft (5,500 m).
  • Diagnostics. Webasto's new heaters work with the Webasto System Diagnostics tool. Contact us if your heater needs service.
  • Use. These kits are sold for land vehicles. If you have a marine use, contact us first.

Which kit is right for you?

Part numberFuelControlDucting in kitHeat range
5014433A (this kit)DieselRheostat dialYes2,400 to 7,000 BTU/h (0.7 to 2.0 kW), boost 8,500 BTU/h (2.5 kW)
5014494ADieselSmarTemp 3.0 BluetoothYes2,400 to 7,000 BTU/h (0.7 to 2.0 kW), boost 8,500 BTU/h (2.5 kW)
5014436AGasolineRheostat dialNo2,730 to 7,000 BTU/h (0.8 to 2.0 kW), boost 8,500 BTU/h (2.5 kW)
5014495AGasolineSmarTemp 3.0 BluetoothYes2,730 to 7,000 BTU/h (0.8 to 2.0 kW), boost 8,500 BTU/h (2.5 kW)

Shipping

Pre-orders are expected to ship between November 20th and December 1st.