by Warren McCullough
The recent easing of virus-related travel restrictions in many parts of the country has seen increasing numbers of motorhomes back on the road – right in the middle of winter!
Those who are able to travel to the northern areas of the continent may be able to avoid the cold weather further south, but the rest of us are likely to be dealing with single digit and below-zero temperatures as we settle in each night. While winter travelling in Australia may not require the insulated water tanks and anti-freezing infrastructure installed in the motorhomes of our northern hemisphere cousins, reliable air heating is still essential, especially when venturing inland or to alpine areas. Three heating options are available in our van:
Roof-mounted air-conditioner
Portable ceramic fan heater
Ducted diesel-fuelled heater.
The roof-mounted air conditioner and the ceramic fan heater both require 240-volts to operate, so are only suitable for use when staying in caravan parks or campgrounds with access to a mains power supply. The diesel heater is fuelled from our van’s main fuel tank and can be used anywhere. A fourth component is also critical to cold weather motorhome comfort: a quality doona, blankets, and warm clothes!
Roof-mounted Air-Conditioner
A heating function is built into our Dometic roof-mounted air conditioner, but the unit requires 240-volts to operate. This is not a ‘reverse-cycle’ air conditioning unit: The heating facility is similar to a regular fan heater – a metal coil element with air blowing over it. This is actually a better heating option than a reverse-cycle heat exchange, which doesn’t function well at very low outside temperatures, which is when you are likely to be using the heater!
I rate the roof-mounted unit as our least preferred heating option. Although silent outside, the fan is relatively loud inside and the thermostat on the fan is either fully on or off (not tapered). Also, it draws air from the ceiling, which is where the warm air already resides.
Portable Ceramic Fan Heater
When mains power is available this is our preferred heating option. The ceramic fan heater is small, sits on the floor at the front of the van (drawing in cooler air from the floor) and is very quiet.
These heaters are also relatively inexpensive – around $20 to $40. We prefer the ceramic variety over regular fan heaters with a heated element, from both a safety perspective and for overall efficiency. While most heaters in this category have similar heating specifications, physical dimensions vary considerably. As a portable fan heater is something that will most likely be stored more often than it is used, choose one that best fits your situation, which usually means purchasing the smallest available. Our heater is 200 mm H x 150 mm W x 100 mm D).
These heaters usually include an adjustable thermostat control with overheat protection, a tip-over shut-off switch and are readily available at Bunnings and most department stores.
Ducted Diesel Heater
We have a Dometic Eberspacher diesel-fuelled air heater installed under the rear seats, with a ducted air outlet in the living area. Our van is relatively small, requiring only one ducted outlet. Larger vans are able to utilise multiple ducted outlets to disperse the heated air over a wider area.
The heating unit draws fuel from our vehicle’s diesel fuel tank, theoretically using up to one and a half litres if left running overnight, although we have never needed to keep it running all night. The diesel heater also uses a couple of amps of battery power to start the heater up, and to keep the fan running.
The unit is quiet inside the van, but can be heard outside when it is starting up. Once the air in the van is up to temperature and the thermostat kicks in, the heater tapers off and the sound output is negligible.
If your van is not diesel fuelled or you have a slide-on camper without easy access to the vehicle’s diesel tank, and you already have LPG installed, then an equivalent LPG-fuelled ducted air heater serves a similar purpose.
Warm Bedding and Clothes
Once the van is up to temperature, good quality bedding keeps us warm for the night as we turn the heater off when we go to bed. Our experience has been that during cold winter nights the internal van environment stays about 5° to 10°C warmer than the outside temperature, although we haven’t experienced any really bitterly cold ‘blizzard’ type conditions on our trips away.
On our most recent inland journey we ran the diesel heater for an hour or so before bedding down for the night, then turned the heater off. First thing in the morning the outside temperature was -2ºC, while the inside air temperature was +8°C, but we were cozy and warm under the bed covers. Running the heater for 15 mins in the morning brought the inside air temperature up to a more respectable +17°C.
The Bottom Line
When camped without mains power, the diesel heater is our go-to air heating option: it warms the air in the van within a few minutes, and is very economical. In campgrounds with mains power available the portable ceramic fan heater warms the van very quickly, is quieter (outside) than the diesel heater and is not consuming diesel fuel. With these two heating options we have no need to use the heating function of our roof-mounted air-conditioner, but I am sure its cooling facility will prove invaluable as we head into a long hot summer!