Diesel vs Gas Heater for Campervans
Heating is not optional in a campervan used year-round in northern and central Europe. Overnight temperatures in the UK, Germany, and the Netherlands regularly fall to 0–5 °C in autumn and spring, and well below freezing in winter. A properly specified heater makes the difference between a cosy night's sleep and a miserable experience. The central question for most builders is whether to go with a diesel-fuelled air heater or an LPG gas heater — and the answer depends on your priorities around fuel availability, installation complexity, running cost, and performance.
How Diesel Air Heaters Work
Diesel heaters use a small combustion chamber that burns fuel drawn from the vehicle's own diesel tank (or a dedicated auxiliary tank). A blower pulls combustion air in, burns it with the injected fuel, and expels exhaust gases out through a separate outlet. A second fan circulates warm air from a heat exchanger into the van interior. The process is entirely sealed — combustion gases never enter the living space — making it safe for unventilated sleeping areas, provided it is installed correctly.
The market is dominated by two German manufacturers: Webasto and Eberspächer (specifically their Espar-branded products in some markets). Both companies have decades of experience supplying OEM heating systems to commercial vehicles, coaches, and passenger cars. Their products are expensive but exceptionally reliable and well-supported across Europe. Budget diesel heaters from Chinese manufacturers (commonly sold under the Vevor, Hcalory, and similar brand names) offer similar functionality at a fraction of the cost but with significant variability in reliability and support.
How Gas (LPG) Heaters Work
Gas heaters burn LPG (a mixture of propane and butane, or propane alone) and can be either blown-air (a fan distributes warm air) or radiant/convection (heat radiates and convects without a fan). For campervans, blown-air gas heaters are the most practical, as they allow heat to be ducted to different areas of the van.
Truma (German) and Propex (British) are the leading gas heater brands for leisure vehicles in Europe. The Truma Combi system is particularly notable — it combines space heating with water heating in a single unit, which is an elegant solution for a van conversion where space is at a premium. Propex heaters are popular in the UK market and have a long track record of reliable, quiet operation.
Running Cost Comparison
Running costs depend on fuel prices, which vary across UK, Germany, and the Netherlands, but the relative economics are broadly consistent.
A mid-size diesel heater (2 kW output) uses approximately 0.1–0.2 litres of diesel per hour at normal output. Diesel in the UK costs around £1.50–£1.60/litre (2025), in Germany around €1.65–€1.80/litre, and in the Netherlands approximately €1.80–€2.00/litre. Running the heater for 8 hours overnight therefore costs approximately:
- UK: £1.20–£2.56 per night
- Germany: €1.32–€2.88 per night
- Netherlands: €1.44–€3.20 per night
LPG gas costs vary considerably. In the UK, a 6 kg butane or propane cylinder costs approximately £20–£30 and contains around 12.5 kWh of energy per kg, so roughly 75 kWh total. A 2 kW gas heater running for 8 hours uses around 16 kWh, which works out to approximately £4.30–£6.40 per night from a small cylinder. Filling a fixed LPG tank at a motorhome service point is cheaper — typically £0.80–£1.20/litre equivalent.
Diesel heating is generally cheaper per night than small-cylinder LPG, particularly when drawing from the vehicle's main fuel tank.
Fuel Availability Across UK, DE, and NL
Diesel is universally available at filling stations across all three markets. Drawing from the vehicle's own tank eliminates the need to carry extra fuel, though some builders prefer a small dedicated diesel tank to avoid running the main vehicle tank too low.
LPG availability is more variable. In the Netherlands, LPG is exceptionally well distributed — the Netherlands has one of the highest densities of LPG forecourt filling points in Europe, largely due to the historical prevalence of LPG-converted passenger cars. Germany also has reasonable LPG filling coverage. In the UK, the network is sparser and has been contracting as LPG car conversions declined; campers relying on a fixed LPG tank need to plan routes more carefully.
Exchangeable gas cylinders (Campingaz, Calor, various local brands) are available at motorhome dealerships, large campsites, and some DIY stores across all three countries, but cylinder standards differ. A UK Calor cylinder uses a different connector from a German or Dutch bottle. If crossing borders, a clip-on universal adaptor or a refillable fixed LPG system is preferable to relying on specific proprietary cylinders.
Installation
Diesel Heater Installation
Installing a diesel heater requires routing a fuel pickup line to the tank, installing an exhaust outlet through the van floor or body, routing a combustion air intake, and connecting the heater to 12V power (the blower fan draws 7–14 A on startup and 2–4 A when running). Installation is achievable for a confident DIY builder but requires care — fuel lines and exhaust routing must meet safety requirements. Professional installation by a certified Webasto or Eberspächer dealer is recommended for those less confident with vehicle fuel systems.
Gas Heater Installation
Gas heater installation requires connecting to an LPG supply (fixed tank or cylinder locker), routing an exhaust flue through the van body, and ensuring adequate combustion air supply. In the UK, gas installations in leisure vehicles should comply with BS EN 1949:2011 standards. Professional installation by a Gas Safe registered engineer is strongly recommended and may be required for insurance purposes. Truma and Propex both provide detailed installation manuals and dealer support networks across Europe.
Noise
Modern Webasto and Eberspächer heaters are very quiet in normal operation — the combustion is near-silent and only the distribution fan is audible, typically at 35–45 dB at one metre. The startup sequence involves a brief glow period and initial higher fan speed, which may be noticeable but lasts only 60–90 seconds.
Truma gas heaters are similarly quiet. Propex heaters are widely praised for their very low noise output — the small fan and burner combination is one of the quietest in the leisure vehicle market.
Budget Chinese diesel heaters are more variable in noise output. Some units produce a noticeable combustion rattle or fan noise that quality units do not. If noise is a concern, investing in a named European brand pays dividends.
Sizing: kW Output by Van Length
Heater output should be matched to the volume of the van space and the target temperature differential (the difference between outside temperature and desired inside temperature). As a practical guide:
| Van Size | Approx. Volume | Recommended Output | Example Models |
|---|---|---|---|
| SWB panel van (up to 4.5 m) | 4–6 m³ | 1.5–2 kW | Webasto Air Top 2000 STC, Propex HS2000 |
| MWB panel van (4.5–5.5 m) | 6–9 m³ | 2–3.5 kW | Eberspächer Airtronic D2, Truma VarioHeat |
| LWB/high-roof van (5.5 m+) | 9–14 m³ | 3.5–5 kW | Webasto Air Top 3500 ST, Eberspächer Airtronic D4 |
These are approximate figures. A well-insulated van needs less heating output; a poorly insulated one needs more. Good insulation is always the first investment — it reduces both heating and cooling loads.
Altitude Performance
Diesel heaters from Webasto and Eberspächer are tested and rated for operation at altitude. The Webasto Air Top 2000 STC, for example, is specified for use up to 5,500 m. Budget Chinese heaters often struggle above 1,500–2,000 m as the thinner air affects combustion, sometimes causing sooting or shutdown. For alpine travel — particularly relevant for those travelling through Switzerland, Austria, or the French Alps — invest in a quality European-branded heater.
Diesel vs Gas: Head-to-Head Comparison
| Feature | Diesel Heater | Gas (LPG) Heater |
|---|---|---|
| Primary brands | Webasto, Eberspächer | Truma, Propex |
| Fuel source | Diesel (vehicle tank or auxiliary) | LPG (cylinder or fixed tank) |
| Running cost (per night) | £1.20–£3.20 | £4.30–£6.40 (small cylinder) |
| Fuel availability (UK) | Universal | Moderate |
| Fuel availability (NL) | Universal | Excellent |
| Installation complexity | Moderate (fuel line routing) | Moderate (gas system required) |
| Altitude performance | Excellent (quality brands) | Good |
| Combined water heating | Some models (e.g. Webasto Dual Top) | Yes (Truma Combi) |
| Entry-level price | £600–£900 (quality brands) | £400–£700 |
Frequently Asked Questions
Is it safe to run a diesel heater while sleeping?
Yes, provided the heater is correctly installed with a sealed combustion chamber and properly routed exhaust. The combustion process is entirely separate from the living space — no carbon monoxide enters the van interior. That said, always fit a carbon monoxide alarm as an independent safety measure, regardless of heater type.
Can I run a gas heater with the van windows closed?
Quality gas heaters for leisure vehicles (Truma, Propex) use a sealed flue system that draws combustion air from outside and exhausts gases outside. They do not consume oxygen from the living space and are safe to use with windows closed. Open-flame gas burners without a flue are not safe for use in a closed vehicle.
What happens if my diesel heater runs out of fuel?
The heater will shut down and may need to be bled and re-primed before it will start again. Some models require a purge cycle to clear air from the fuel line. Draw fuel from the vehicle tank and leave a reasonable buffer — do not let the tank run below the last 10–15 litres.
Can I install a diesel heater myself?
DIY installation is legally permissible in the UK and most of Europe for diesel heaters (unlike gas, which requires professional certification). However, fuel line routing and exhaust installation carry real safety implications. If you are not confident with vehicle fuel systems, have the installation checked by a professional.
Do diesel heaters work in petrol vans?
No — diesel heaters require diesel fuel. If your conversion vehicle has a petrol engine, you will need either a dedicated auxiliary diesel tank or a gas heater instead.
