An affordable diesel heating solution designed to keep off-grid travellers warm when the temperature drops.
It was the winter of 2021. We were driving south into Alice Springs when the city went into a snap COVID lockdown. To avoid getting stuck, we turned right off the Stuart Highway and hightailed it to the West MacDonnell Ranges, riding out the short-lived lockdown at a free camp on the Finke River/Larapinta.
The setting was idyllic, but nothing prepared us for the frigid overnight conditions. In the morning the temperature hovered just above freezing and the cold was paralysing, rising through the floor of our poorly insulated caravan. It was then that we decided we needed a diesel heater.
The years passed, most of our trips were limited to warmer climes (or seasons), and powered caravan park sites became our go-to stays in winter. But we longed for off-grid bush camps. This winter it was finally time to take the plunge.
CHOOSING A HEATER
Our caravan has a moderate power system (400W solar, 200Ah lithium battery, 2,000W inverter), but it’s not enough to run our split-system air-conditioner. In any case, a diesel heater is much more energy efficient. We’d seen top-of-the-range German-made Eberspacher units retailing for over $2,000, and dirt-cheap Chinese imports for less than $200. We wanted something in between. A quality heater, made to Australian standards that wouldn’t blow smoke on our neighbours or sound like a jumbo preparing for take-off.
Our caravan servicing technician recommended local Melbourne supplier and installer Red’s Diesel Heaters, who suggested the AU Focus Diesel Heater. AU Focus is an Australian-owned brand, backed by a two-year warranty, with local support and servicing. They’re also used in more than 90 RV brands around the country. This was important to us for quality assurance.
We had the option of 2kW or 5kW unit. Our 22-foot caravan was borderline, but installer Brett Watts said heaters function better when working harder, so we opted for the smaller model. We could have installed it ourselves – many people do and the heater comes with an installation kit – but this kind of DIY is not our forte, and the idea of cutting holes in our caravan floor gave me shivers.
THE INSTALLATION
The AU Focus heater has four main components. The core unit, containing the heating element and fan, is about the size of a small shoebox and is mounted and vented under the bed. We bought an optional cover for protection and air circulation. The five-litre stainless steel fuel tank is mounted on the side of our toolbox on the drawbar and has a lockable fuel cap, gauge and discreet checkerplate cover (optional). There’s an exhaust venting to the van’s offside (with muffler), and an LCD control panel and thermostat installed above the bedside table. The fuel pump and fuel and 12V lines are hidden out of sight. The heater also comes with a remote-control fob and Bluetooth connectivity for operating with a smartphone via the app. Installation at our home took Brett about four hours.
FIRING UP
The first big test of our new heater comes on a trip to Hepburn Springs in the middle of a Victorian winter. We’re free camping and it’s bitterly cold. At 7am it’s 6°C outside with a “feels like” temperature of 0.8°C. According to the heater’s thermostat, the air temperature inside the caravan is barely above double figures. I tap the heater on; a soft, warming hum kicks in underneath the bed and within five minutes the chill has gone from the room. The thermostat is set to 20°C, and it takes a good 45 minutes to come to temperature. This would be reduced if we had a larger unit with a second duct, but we don’t see the need. By the time we’re ready to get up and dressed, the caravan is warm and toasty.
The heater has three modes: manual, smart and fan. All are controlled by the LCD panel, while manual and smart modes can also be managed by the remote-control fob and the phone app. There’s a dial to toggle between the settings. We only use smart mode; it’s the simplest function and enables us to preset the temperature and not have to worry about the fan speed, which adjusts automatically. When the temperature is reached, the heater stops burning diesel and the fan runs at a low RPM, kicking back in when the thermostat drops 2°C below the set temperature.
The heater can also be programmed to turn on and off at a set time, which is handy if you want the caravan to be warm before you wake up, although not really necessary in such a small space when you have phone connectivity. I don’t think we would ever sleep with the heater running overnight – although it is possible – as the sound of it switching on and off under the bed would be disruptive. That said, I’m surprised by how quiet the unit is – like a soft-idling small car, but the noise would be amplified at night.
The other surprising feature of the AU Focus heater is its fuel efficiency. Over the course of three days, using the heater mornings, evenings and one full day, we use less than a quarter of a tank of diesel. Likewise, the drain on our battery (from the pump and fan) is negligible.
THE VERDICT
This is one of those purchases I really wish we’d made years ago. The AU Focus is a relatively inexpensive heating solution that’s a game changer for off-grid winter travel. It’s quiet, efficient and intuitive, and will definitely expand our cold-climate horizons.
SPECIFICATIONS
AU Focus Diesel Heater Kit 2kW MZ
Heater unit – 340mm (L) x 115mm (W) x 115mm (H)
Fuel – 5L stainless steel tank
Fuel consumption – 0.1-0.3 L/h
Power – 12V 5-35W (90-150W peak start up)
Optional extras – unit cover, checkerplate fuel cover
Warranty – two years
RRP: $749
We paid: $1,540 installed, including fuel and extras
aufocus.com.au
