Autoterm Air 4D (Planar 44D) diesel parking heater & selectable Control Panel

The diesel-fired Autoterm Air 4D air heaters have become a standard choice in campers, motorhomes and expedition vehicles. They are designed for continuous operation and work with a high level of safety and reliability. With low fuel and power consumption, they provide controllable heating for both small and large leisure vehicles, on land and on the water.

Thanks to the existing E-mark approval, installation of these heaters does not require a TÜV inspection or registration. The installation itself can also be carried out by non-professionals during a self-build camper conversion without voiding the warranty.
Installation must be carried out in accordance with the manufacturer's installation instructions. Of course, our installation partners are also happy to carry out the work for you if needed.

Do you need 4 kW of heating output?

The heating output of the Air 4D can quickly turn small or well-insulated interiors into a sauna, meaning you may end up heating with the window open. So it is worth considering carefully whether you really need 4 kW, or whether the 2 kW version of this heater would be sufficient for your use.

4 kW is the right choice for you if

• the interior of your camper is relatively large, from approx. 14 - 16 cubic metres of heated interior volume without furniture
• your vehicle is poorly insulated and you do not want to change that anymore
• you regularly travel in very cold regions
• you deliberately need more reserve capacity than a 2 kW heater can offer for demanding conditions

If you occasionally really do need the full 4 kW, but often also need finely adjustable lower output for mild temperatures, a 2 x 2 kW setup is perfect for you. Take a look at the TWIN Kit here.

Both heater sizes are available for 12 V and 24 V on-board electrical systems – simply choose the appropriate version.

E-mark approval

The Autoterm Air 4D has E-mark approval (e2). This means it can be installed without registration, and no inspection or approval by TÜV is required.

Robust and easy to repair

Autoterm air heaters are designed for continuous operation. Running throughout an entire trip is not a problem for them, and they are extremely reliable.

If a repair should nevertheless become necessary, we are there for you as a service partner and German distributor with our own workshop. However, if you are travelling around the world, you can even carry out certain repairs yourself in an emergency – the heater does not need to be removed and sent in. This is a major advantage, especially for overlanders and long-distance travellers.

Altitude kit integrated

Autoterm diesel air heaters are also suitable for use at high elevations. The integrated altitude kit adjusts the amount of injected diesel fully automatically according to ambient air pressure.

We successfully tested the altitude kit ourselves at an elevation of 3440 m on the Pitztal Glacier before it went into series production. Since then, our customers have travelled much higher with it. Fabian, for example, with his VW T3 “Tornado on Tour”. He tested the heater, which was still called the Autoterm Planar 2D at the time, in his van in Chile at 5032 m – only Tibet takes you higher.

Even at this extreme altitude, the Air altitude kit worked flawlessly. You can watch his filmed heater test here on YouTube.

So your heater will not let you down when things get rough at altitude.

Please note

Even with an altitude kit, operating a diesel air heater – just like operating a diesel engine in a vehicle – remains a technical compromise. After some time, the combustion chamber must be heated up properly again so that the heater can burn off the first signs of soot build-up. So even with an altitude kit, soot build-up cannot be avoided completely.

If you really do spend several weeks at 4000 m altitude, cleaning the combustion chamber and replacing the seals is possible and acceptable for use under such conditions.

Good to know: at high altitude, the heater gets less air and therefore correspondingly less fuel. As a result, it cannot deliver full output at high elevations. As a rule of thumb: above 2000 m, you lose around 5% of output per additional 500 m.

Under such extreme conditions, free fan operation becomes especially important. In theory, it would work best without any warm air ducting at all. If you plan to travel in these conditions, keep the warm air distribution as simple as possible – short and with few bends.

Combustion air intake and exhaust should be kept extremely short and low in resistance. Avoid kinks, blockages and reductions.

Burn-off also at low altitude

Burning the heater clean is the most important and at the same time the only maintenance the heater really needs.

Soot build-up generally occurs when the heater is run at low output or is switched on and off frequently – just like a diesel engine in a vehicle. The heater should therefore be run at full output for half an hour every 1 to 2 weeks at the latest so the combustion chamber can clear again – similar to a brisk motorway drive.

Control and operating elements

A control panel is included with the heater. You can choose from the following versions:

Comfort Control

Control panel with multifunction rotary knob and display: easy operation, timer function, voltage display and thermostat mode – it is the proven all-rounder and also features a burn-off reminder and voltage monitoring, which can actively switch off the heater to protect the battery.

Touch Control

Modern touch control panel with clear menu structure. Ideal if you value especially convenient and intuitive operation and like to keep all information in view.

Mini Control

The Mini Control is a simple control panel for operating the heater via output levels. Using temperature mode with this control panel requires an optional external temperature sensor.

Tip: optionally available Push Control

Since 2025, two control elements can be operated at the same time on one heater – for example one in the living area and one in the cab or sleeping area.

The Push Control panel is a compact, robust push-button unit for quick day-to-day operation (on/off and output levels). It can be combined with the Comfort Control or used on its own if only minimal operating functions are required.

Compare control panels directly

You can find a detailed comparison of the control panels in our magazine:
Autoterm control panels compared – functions, differences and recommendations (available in German - we kindly ask to use your Browsers translation)

Optional: extension cables

The cable length of the included control panels is 1.80 m. Longer cables or extension leads can be found in our air heater accessories.

Remote control

The heater has an emergency switching input on the wiring harness, which is often used for custom remote control solutions. All that is required is to connect two wires via a switch or relay. There are two control options. First: continuous connection. In this case, the heater starts and runs until the connection is interrupted again. Second: pulse control. Here, a push-button pulse of 0.5 - 3 s can be used to switch the heater on. The next pulse switches it off again.

The advantage of the second option is that it allows the heater to be controlled using different operating elements. For example, you can switch it on using a custom-built remote control or a push button and later adjust the output level or switch it off from bed using the control panel. Or of course the other way around.

Technical data

Operating voltage: 12 V / 24 V (please select accordingly)
Heating output: 1 kW (min), 4 kW (max)
Air flow rate: 70 m³/h (min), 120 m³/h (max)
Fuel consumption: 0.12 l/h (min), 0.514 l/h (max)
Power consumption: 10 W (min), 62 W (max)
Air inlet: 80 / 83 mm
Hot air outlet: 96 / 100 mm

Dimensions: 402 x 157 x 188 mm
Weight of the heater without accessories: 5.5 kg

Scope of delivery

The scope of delivery includes everything required for installing the Autoterm Air 4D.

• Heater unit 12 V / 24 V (please select according to your on-board system voltage)
• Control panel (please choose your preferred version)
• Autoterm fuel pump “Extra Quiet”
• Exhaust silencer (17 x 9 x 5 cm)
• Rubber mount for metering pump
• Wiring harness for metering pump
• Wiring harness for heater unit
• Combustion air intake hose with integrated silencer
• Heat protection hose
• Exhaust pipe end piece + clamp
• Tank pick-up pipe
• 5.5 m fuel line
• Fuel line connector
• 1 m metal flexible exhaust pipe
• Screws, nuts, clamps, heat-shrink tubing, cable ties
• Operating instructions

Important: fuel hose

The delivery also includes fuel hose for use as a line connector. The length is usually completely sufficient. If it should still not be enough, you can reorder the hose by the metre under item number 35612.

Optional / recommended

For even easier installation, with thermal decoupling of the heater as an added benefit, take a look at our mounting flanges or choose one of our ready-configured installation kits straight away.

Installation

Installation may also be carried out by non-professionals without voiding the warranty. So you are not required to have the air heater installed by a workshop.
Installation must be carried out properly and in accordance with the manufacturer's installation instructions.

Of course, our installation partners are also available if you do not want to install it yourself.
 

Installation tips & information

Do’s and don’ts when installing an air heater

Autoterm heater FAQ

Replacing Eberspächer or Webasto air heaters

The hole pattern of the Autoterm Air 4D matches that of the air heaters commonly installed at the factory by Eberspächer or Webasto. This means replacement is possible without drilling new holes in the bodywork.