maXpeedingrods 8KW Bluetooth Heater
#1 in SplitFull review
A bargain split heater for a van, RV or workshop on a budget. Expect closer to 5 kW than the 8 kW on the box, and no stated warranty.
Amazon $95.99$95.99
A diesel heater (also called a parking heater or air heater) burns a small amount of diesel in a sealed chamber and blows the heat into a van, truck cab, RV, boat, tent or garage. The exhaust goes outside through its own pipe, so the air inside stays dry, and a 12 V battery only has to run the fan, fuel pump and controls. One sips roughly 0.1 to 0.5 liters of diesel an hour.
They come in two builds. A split heater is installed under the floor or a seat, with a separate fuel tank and ducting, the way Webasto and Espar heaters have been fitted to trucks for decades. An all-in-one heater puts the heater, tank and controls in one portable case you set down outside a tent or in a workshop, with the exhaust pipe pointed outside.
Most of the cheap heaters sold as 5, 8 or even 12 kW share the same roughly 5 kW core. Diesel holds about 10 kWh of energy per liter, so a heater can’t put out more heat than its own fuel burn supplies. When a rating is higher than that, we score the heater on what its fuel burn gives at a type-approved heater’s efficiency instead, and say so on its page.
Top Picks
Espar Airtronic S3 D2L
#2 in SplitFull review
For van, truck and boat owners who want a quiet, type-approved 2 kW heater that works at high altitude. It costs much more than clones but is built to run for thousands of hours.
Amazon $1,250$1,250
Shop by Type
Split
36 rankedHeaters installed under the floor or a seat, with a separate fuel tank and ducting: for vans, trucks, RVs and boats.
Top rated: maXpeedingrods 8KW Bluetooth Heater $95.99
All in one
34 rankedPortable heaters with the tank, battery box and controls in one case: for tents, garages, workshops and vans with no install.
Top rated: Autoterm Air 2D Portable $1,599.99
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Prices were last checked October 30, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Best Split Diesel Heaters
- maXpeedingrods 8KW Bluetooth Heater#1 of 36Full review
A bargain split heater for a van, RV or workshop on a budget. Expect closer to 5 kW than the 8 kW on the box, and no stated warranty.
Amazon $95.99$95.99~5 kW-No9 L - Espar Airtronic S3 D2L#2 of 36Full review
For van, truck and boat owners who want a quiet, type-approved 2 kW heater that works at high altitude. It costs much more than clones but is built to run for thousands of hours.
Amazon $1,250$1,2502.2 kW27 WYes- - Autoterm Air 2D#3 of 36Full review
For van and boat owners who want a type-approved 2 kW heater for less than Webasto or Espar. Add a timer panel if you want it warm before you wake.
Amazon $949.99$949.992 kW29 WYes- - Espar Airtronic S2 D2L#4 of 36Full review
For van and truck owners who want a type-approved 2 kW heater with low power draw and a timer. The newer Airtronic S3 D2L now does the same job for less.
Amazon $1,315$1,3152.2 kW31 WYes- - Espar Airtronic M3 D4L#5 of 36Full review
For larger vans, trucks and boats that need a type-approved 4 kW heater that works anywhere, including high mountain passes. It costs far more than clones but is built for years of daily use.
Amazon $1,675$1,6754 kW37 WYes-
Best All-in-One Diesel Heaters
- Autoterm Air 2D Portable#1 of 34Full review
For overlanders, ice fishers and boat owners who want a portable heater with a proven, type-approved core and will pay for it. Clone all-in-ones give similar heat for a fraction of the price.
Amazon $1,599.99$1,599.992 kW29 WYes- - Mudiro M-5S Ultra Diesel Heater#2 of 34Full review
A cheap all-in-one heater for tents, garages and vans that adds a CO shutoff and automatic altitude adjustment, though its real output is well under the 8 kW rating.
Amazon $129.99$129.99~2.9 kW-No5 L - Sokaiso 8kW App Diesel Heater#3 of 34Full review
A very cheap heater with thermostat, app control and a two year warranty, for tents, garages and occasional van use. Expect closer to 4.2 kW than the 8 kW on the box.
Amazon $77.69$77.69~4.2 kW-No5 L - VEVOR XMZ-L-D3 8kW All-in-One Heater#4 of 34Full review
A cheap upright all-in-one heater with an app, timer and automatic altitude adjustment, for tents, garages and high-country camping. Expect well under its 8 kW rating.
Amazon $101$101~5 kW40 WNo5 L - GEARLASSO DH002 Diesel Heater#5 of 34Full review
A cheap all-in-one heater with app control and a two year warranty, for tents and small vans, with real output closer to 3.6 kW.
Amazon $139.99$139.99~3.6 kW-No5 L
How We Rank
Each heater is ranked against others of the same build, and scored on its price per credible kilowatt, whether it’s type approved to the vehicle heater standard, its controls and safety features, how much power it draws from the battery, its warranty and how gently it can run.
| Factor | Measures | Weight |
|---|---|---|
| Value | price per credible kilowatt | 25% |
| Type approval | ECE R122 approval for vehicle heaters | 20% |
| Controls and safety | thermostat, CO shutoff, altitude, app, timer | 15% |
| Power draw | battery drain while running | 15% |
| Warranty | warranty length | 15% |
| Low setting | how gently it can run in a small space | 10% |
How we rank explains each factor in full.
Any fuel-burning heater can leak carbon monoxide if its exhaust or seals fail. Run the exhaust outside, keep the air intake away from it, and fit a separate CO alarm wherever people sleep, even if the heater has its own sensor.