Best Split Diesel Heaters Ranked

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.

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.

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.

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.

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.

For larger vans, sleeper cabs and boats that need a type-approved 4 kW heater with a wide turndown. The M3 D4L that replaces it costs the same and draws less power.

For van and truck owners who want a new type-approved 2 kW heater with altitude adjustment and a very low idle setting, or a drop-in replacement for an Air Top 2000 STC. It costs far more than clone heaters of the same size.

A cheap small split heater for a van, truck cab or small boat cabin. Its fuel burn backs up the 2 kW rating, but the maker gives no warranty length or power figures.

A cheap split kit with Bluetooth control and automatic altitude adjustment, for DIY installs in vans and campers that travel high. Real output is far below 8 kW.

A bargain split heater kit for a van, truck or camper install, with app control and a thermostat. Expect about 3.5 kW of heat, not 8.

For motorhomes and boats with long, branching duct runs that a standard 4 kW heater can not push through. Otherwise the D4L is cheaper and draws less power.

A well-featured split heater for van and RV builds that want automatic altitude handling and a big tank; expect about 3 kW of real heat, not 8.

For 24V trucks, buses and larger motorhomes that need a type-approved 5 kW heater with automatic altitude adjustment. It costs far more than clone heaters of the same size.

A small, cheap split heater with Bluetooth control and automatic altitude adjustment, sized for cars, small vans and boat cabins.

A complete split kit with a big tank and remote for trucks, trailers and boats, but it is a generic clone priced well above others like it.

For 24V trucks and buses that need a type-approved 4 kW heater with automatic altitude adjustment. The high price buys Webasto build quality and approval, not more heat.

A bare-bones, very cheap split heater kit for DIY installs in trucks, campers and boats at low altitude. Real output is closer to 3 kW than 8.

A very cheap complete split kit with thermostat mode and a remote, for DIY installs in RVs, garages and trucks. Specs and support are thin.

A bare-bones split heater for DIY installs in trucks, RVs and boats on a tight budget. Real output is closer to 3 kW than 8.

A quieter brushless take on the Chinese split heater for vans and RVs. Expect about 3 kW of heat, and few published specs to check it against.

An aluminum cased split kit with an honest 5 kW rating, a big tank and a remote, for truck cabs and campers. It costs more than most clones.

A small, cheap split heater for cars, truck cabs and boat cabins, with a credible 2 kW rating and a 12V or 24V supply.

A low cost 5 kW split kit for DIY truck and RV installs, sold with almost no published specs or warranty.

An aluminum cased split kit with a big tank and remote for truckers and RVers who want a sturdier clone. Its real output matches the cheaper 5 kW model.

A basic 5 kW split kit for truck, RV and boat installs, with a timer but no thermostat.

A budget 5 kW split kit with tank and remote for cars, vans and small shops, with few published specs to back it up.

A well documented budget split heater for a van, camper or truck, with a big tank and a low power draw. Treat it as about a 3 kW heater, not 8 kW.

A low cost split heater kit for a van, truck or RV that wants WiFi control and a big tank. Treat it as about a 4 kW heater, not 8 kW.

A brushless split heater with automatic altitude adjustment for vans, trucks and RVs at 12V. The listing publishes too few figures to judge its real output.

A quieter 5 kW split heater with a thermostat and plateau mode for van and RV builds, at a premium over basic kits.

A brushless split heater with automatic altitude adjustment for vans, trucks and RVs at 12V. The listing publishes too few figures to judge its real output.

A compact 2 kW split heater for car and small truck cabs, though it costs as much as LF Bros’s 5 kW kit.

A cheap app-controlled split heater for DIY van and RV installs, though Hcalory publishes few specs for this 5 kW version.

A bare bones split heater for DIY installers in the mountains who want automatic altitude adjustment at the lowest price. The short warranty and missing specs make it a gamble.

A cheap split kit with its own tank and automatic altitude adjustment, for DIY van and truck builds at elevation. The 3 month warranty is the catch.

For van, truck and boat owners who want a type-approved, proven 2 kW heater with low power draw. Production has ended, so check that the seller still offers support.