Beaches, searing midday heat and swatting mozzies in the middle of the bush. This is a foreigner’s take on Australia, but we locals know there’s so much more than this. Temperatures do drop below zero in large parts of the country (ask anyone from Tassie or our Bush capital) and winter chills are part of everyday hassles. For anyone set on touring this great land, possibly doing the 15000 odd kilometres of the Big Lap, having a little warmth in the caravan or motorhome is one necessity often left out. Relying solely on the AC will drain all the juice in batteries, creating that homely feeling just in time for morning coffee. Other solutions are cheaper, more efficient and bring the needed warmth in that much faster.

A simple remedy for cold temps is a diesel heater. These are cheap and easy to use and maintain and can heat your rig for a couple of dollars a day. They’re also safe, quiet and simple to use. Installing one in your caravan or RV doesn’t require an engineering degree, There are also different variants to suit most use cases, with a portable diesel heater taking up little space and offering a lot in the way of convenience.

What a Diesel Heater is and How It Works

A diesel heater is a heating device using diesel as its primary fuel source. It gets temperatures inside cars, trucks, campervans and motorhomes to cozy levels within moments of being turned on. The working principle of diesel heaters is fairly simple. Inside the heater, there is a burner that applies heat to the surface of a heat exchanger. A fan draws air from the outside via an intake hose, and passes it over the heat exchanger to warm it up. The spent exhaust fumes are kept outside, so safety isn’t a concern.

What’s in the Box?

portable diesel heater

Besides the heater itself (with the heater case, combustion chamber and the radiating fins making up the heat exchanger) and where all the fun stuff happens, getting warm air inside involves a few other parts. Heaters are supplied with a fuel tank storing the diesel, a pump to push the fuel to the heater, hosing and ducts in the right lengths that connect the two units, a system of intake and exhaust ducts, filters and mufflers to redirect exhaust gases out, keep warm air in and everything whisper quiet, and lastly, wiring harnesses, cables and Anderson plugs connecting the whole assembly to a 12V or 24V battery. Both a standard and portable diesel heater will also have some way of controlling everything that’s going on. This is delegated to a control board with all the electronics to control things like temperature settings, fan speeds, and pump pressure and can include a handy remote to turn the heater on or off and adjust the temperature.

Benefits of Diesel Heaters

The pros outweigh the cons when it comes to diesel heaters, and when you compare these to the alternatives like LPG and traditional aircons.

  • Safety – diesel ignites when compressed, so heaters using diesel are much safer than petrol heaters as well as those running on LPG. Any diesel leak won’t necessarily cause a fire or explosion which is not the case with petrol or LPG heaters. Most units have built-in safety features to cut off the diesel reaching the combustion chamber in case of a fault.
  • Very Quick Heating – Temperatures get really warm really quickly. And this can be adjusted with varying fan speeds.
  • Low Fuel Use – Users get virtually free heating, with the heater relying on about 1 litre of diesel during a whole working cycle of roughly 4 hours. Compared to other heating sources, this is a very small price to pay for comfort.
  • Convenience – considering that most campervans and caravans are pulled by diesel utes, and most motorhomes use the same fuel, you’ll never be running out of fuel. Though heaters have their own tank, they can also draw fuel from the vehicle if needed.
  • Quiet – Diesel heaters work almost silently, so you won’t be disturbed by rumbling noises in the middle of the night. Sealing gaskets and mufflers do double the duty of silencing the exhaust systems and reducing vibrations.
  • No Condensation Buildup – The dry heat these heaters provide is a boon for preventing condensation inside your motorhome or caravan, so no worries about related health issues or mould and bacteria buildup in the long run.
  • No Fumes – While diesel air heaters are located in the interior, sturdy metal piping gets rid of exhaust fumes to the outside of your rig. There are no nasty smells either.

What to Look for?

To get the most out of your purchase and bring the comfort and convenience of other caravanning necessities such as water filtration systems, heaters need to be built to a standard, comply with safety standards and be easy to use. The most important things to look for in a diesel heater are the rated output, fuel consumption, size and weight, the rated voltage, and all the goodies needed for correct installation. Most heaters are in the 2 to 2.2kW range and will be more than adequate for heating the interior of all campervans and caravans currently used in Australia. There are however 8kw systems for bigger vehicles, but these are generally overkill. Fuel usage is low in all units, averaging anywhere between 150 to 300ml of diesel per hour and dependent on the chosen temperature setting and outside conditions. Though fuel use will rise slightly with altitudes, this is nothing to worry about, even when using the heater in the Snowys.

Dimensions are small for all units, roughly the size of an auxiliary battery, so the heater is easy to install and store even in the typically confined settings in outdoor recreational vehicles. They’re also light, weighing less than 10 kilos in bigger variants and under 5 in portable heaters. Lastly consider the battery setup for connecting the heater. Most can run either 12 or 24V. Heaters can be set up easily with the right installation kit, so check that everything you’re getting fits with your vehicle.