Diesel Heater vs Heat Pump for Campervan Heating: Pros, Cons, and Real Cost Comparison

Cold-weather van life is one of the most rewarding experiences on the road — until your heating system lets you down at 2 a.m. at 9,000 feet. Choosing between a diesel or gasoline air heater and a heat pump for your campervan conversion is one of the most consequential decisions you'll make during your build. Both systems work, but they work differently, cost differently, and suit different travel styles. This guide breaks down the real-world differences so you can make the right call for your rig.

How Each System Works

Diesel/Gasoline Air Heaters

A diesel or gasoline air heater — sometimes called a parking heater or fuel-burning heater — draws diesel fuel from your vehicle's tank (or a dedicated auxiliary tank), combusts it in a sealed chamber, and blows the resulting heat into your van's living space. The combustion exhaust exits through a dedicated flue pipe, keeping fumes completely outside. Units like the Velit Air Heater (4,000W / 14,000 BTU) represent the current generation of these systems: compact, programmable, and capable of heating a full-size van interior from freezing temperatures in under ten minutes. The key characteristic of diesel heaters is that they are largely energy-independent — they consume very little 12V power (typically 10–25W during steady-state operation) while generating substantial heat through combustion.

Heat Pumps for Van Conversions

A heat pump doesn't generate heat through combustion. Instead, it moves heat energy from the outside air into your van using a refrigerant cycle — the same physics that runs your home's HVAC system, just packaged for mobile use. Units like the Dometic 48V FreshJet or GREE EcoCool are engineered for van and RV applications, offering both heating and cooling from a single rooftop unit.

The trade-off: heat pumps require significant power to operate, typically 800–1,500W or more depending on ambient conditions. That means they're best paired with a robust power station or shore power connection. Systems like the BLUETTI RVSolar 48V Power System paired with solar panels are becoming common in full-time van conversions specifically to support heat pump operation.

Performance in Cold Weather: The Critical Difference

This is where the two technologies diverge most sharply. Heat pumps extract warmth from outdoor air, and as outdoor temperatures drop, efficiency (measured as COP — Coefficient of Performance) falls with them. Most residential heat pumps struggle below 20°F (-7°C). While newer RV-grade heat pumps have improved cold-weather performance, most are rated only to around 26-32°F for heating, with noticeably reduced output below that threshold.

Diesel or gasoline air heaters, by contrast, are thermodynamically indifferent to outdoor temperature. A quality diesel heater performs identically at -40°F as it does at 30°F — a critical advantage for overlanders camping in mountain passes, Canadian winters, or high-altitude desert nights. If cold-weather capability is your primary concern, diesel heaters hold a clear technical advantage.

Cost to Run: Real Numbers

Understanding running costs requires looking at fuel consumption and energy prices in your region. Here are representative estimates based on typical operating conditions:

Diesel Heater Running Cost

• Fuel consumption: Approximately 0.1–0.5 liters per hour depending on output level
• Average consumption at medium output: ~0.25 L/hr
• Diesel price (US average): ~$3.80/gallon (~$1.00/liter)
• Estimated cost per hour at medium output: ~$0.25/hr
• Overnight (8 hours at medium output): ~$2.00

Heat Pump Running Cost (Battery-Powered)

• Power draw: Approximately 800–1,400W depending on conditions and setpoint
• Electricity cost (via solar/battery replacement cost): This varies widely based on your system
• If plugged into shore power at $0.14/kWh: ~$0.14–0.20/hr at moderate conditions
• If running from battery: A 1,000W draw over 8 hours = 8 kWh consumed, which requires substantial solar or generator recharge capacity

On pure running cost, shore-powered heat pumps can be cheaper per hour than diesel. Off-grid, aside from cost, the comparison shifts depending on your solar array and battery bank capacity.

Diesel heaters win decisively in off-grid and boondocking scenarios.

Installation Complexity

Diesel Heater Installation

A diesel air heater installation involves: mounting the unit (typically under a seat or in a storage bay), running a fuel line to your diesel source, installing an intake and exhaust flue through your van's floor or side panel, and connecting to your 12V system. Experienced van builders typically complete the installation in four to eight hours. The Velit Air Heater includes the full installation kit, and a digital controller with programmable timers, making thermostat-style scheduling straightforward.

Diesel heaters' total installed cost including unit and components typically ranges from $400–$900 depending on the quality of the heater and accessories chosen.

Heat Pump Installation

Rooftop heat pump installation requires cutting a roof penetration — a more permanent and commitment-heavy modification. Wiring requirements can be more demanding: for a shore power unit, you'll need an inverter capable of handling the higher draw, appropriate fusing, and a battery bank large enough to sustain operation overnight without draining to unsafe levels.

Total installed costs, including compatible power station, can range from $2,500–$6,000+ depending on capacity. The upside is a dual-function system: the same unit that heats you in winter cools you in summer.

Which Should You Choose?

Choose a Diesel or Gasoline Air Heater If:

• You frequently camp off-grid without shore power access
• Your adventures take you to sub-freezing temperatures
• You're budget-conscious on upfront installation cost
• You prioritize heating-only capability and simplicity
• You're a weekend warrior who wants reliable heat without a large electrical system overhaul

Choose a Heat Pump If:

• You need year-round climate control (heating and cooling)
• You have a robust solar-and-battery setup or frequent shore power access
• You primarily travel in temperate climates with mild winters
• You're building a high-end conversion and want an integrated HVAC solution

Consider Running Both

Many serious full-time van lifers run both systems — a diesel heater for cold nights in remote locations and a heat pump for summer cooling and shoulder-season comfort. This combination provides redundancy and climate versatility, and it's increasingly popular among experienced builders who have learned the limits of relying on a single heating and cooling strategy.

Where ROAMiQ Fits In

Regardless of which heating system you choose, managing and monitoring it alongside your battery bank, solar input, and shore power connections becomes exponentially easier with an integrated control monitoring system. ROAMiQ — the multiplex monitoring and control platform — gives van builders real-time control and visibility into each component and appliance, all from a touchscreen display or mobile app, from anywhere in the world. If you're running a heat pump drawing 1,000W from your battery bank, knowing exactly how much capacity remains and how fast your solar is replenishing it isn't just convenient — it's the difference between waking up warm and waking up with a dead battery in January. ROAMiQ integrates naturally with both heating approaches, helping you make smarter decisions about when to run which system.

Frequently Asked Questions

Can I run a diesel heater in a campervan safely?

Yes — when properly installed, diesel air heaters are safe for van use because the combustion process is sealed and the exhaust is vented to the outside. No combustion gases enter the living space. That said, installation quality matters significantly. The fuel line, exhaust flue, and air intake must all be correctly routed and secured. Follow manufacturer guidelines and, if in doubt, have the installation inspected by an experienced van builder.

What temperature can a diesel air heater handle?

Quality diesel air heaters like the Velit are designed to operate in extreme cold — many are rated to start and run in temperatures below -40°F (-40°C). This is one of their primary advantages over heat pumps for cold-climate use. Fuel gelling can be a concern at extreme temperatures, so using winter-blend diesel or adding anti-gel additives is recommended when camping in very cold conditions.

How much power does a diesel heater use from my van's battery?

Diesel heaters use surprisingly little 12V power during steady-state operation — typically 10–25 watts once the unit is running. Startup and ignition draw more (sometimes 8–10 amps briefly), but sustained operation is gentle on your battery bank. This makes them highly compatible with modest electrical systems.

Are heat pumps effective for van conversions in cold climates?

Most RV-grade heat pumps are rated for heating down to approximately 26-32°F and lose efficiency as temperatures drop toward that threshold. For van lifers who primarily camp in mild or warm climates and only encounter occasional cool nights, a heat pump is a practical all-in-one climate solution. For those regularly camping in sub-freezing temperatures, a diesel heater is a more reliable primary heat source.

What's the Velit Air Heater, and how does it compare to other diesel heaters?

The Velit Air Heater offered by RackUp+Go is a 4,000W (14,000 BTU) diesel parking heater designed specifically for campervan and vehicle applications. It includes a digital programmable controller, operates quietly relative to comparable units, and is sized appropriately to heat a full-size cargo van interior efficiently. It represents a mid-to-upper tier option in the diesel heater market, offering a step up in build quality and feature set compared to entry-level imported heaters while remaining more accessible in price than premium European alternatives.

Ready to Heat Your Van Build Right?

Whether you're leaning toward the fuel-efficient simplicity of the Velit Air Heater or the year-round versatility of a heat pump bundle, RackUp+Go has the components, expertise, and systems to support your build. Explore our heating and climate control options at rackupgo.com, and if you're designing a complete electrical system, ask us how ROAMiQ can give you full visibility over every watt and every degree in your rig.