Diesel heaters

Diesel heaters (also known as Chinese diesel heaters/CDH) are a very popular way to heat your vehicle while it is parked. (They're also frequently used to heat garages, sheds, tiny homes, and more, but that's outside the scope of this wiki.) The least expensive heaters cost ~$100, and they use very little fuel. Unlike portable propane heaters, another popular heating option, diesel heaters don't create condensation in your living space. All diesel heaters must be vented to the outside of the vehicle and should be permanently installed for best results. Diesel heaters are a type of parking heater.

Advantages

Diesel fuel is energy dense and burns very hot, making it the ideal candidate for powering a ventilated heater.

A major benefit of diesel heaters for nomads is the fact that they produce a dry heat, which is important to control humidity. Condensation is a significant challenge for living in a vehicle in the winter, even in dry climates. Other dry heat producers include wood stoves and electric heat. Most propane heaters produce a lot of condensation as a product of combustion.

Disadvantages

Diesel heaters require a fair amount of power to start and warm up (usually about 15 Amps), so you'll need an electrical system capable of supporting it, or you'll need to be connected to shore power. (Once warmed up, they require much less power, possibly less than an electric blanket, while still being able to easily heat your entire living space.) Starting a diesel heater from the auxiliary power outlet (cigarette lighter), either from your vehicle or on a portable power station, will probably not work. Running any kind of heater from your main vehicle battery is not recommended.

This disadvantage can be removed with an self-powered or self-generating diesel heater, relatively new to market, which contain their own battery that recharges while in use. The Houswin heater is one such product. At $1200-1500, these are much more expensive than most standalone heaters, but the convenience may be worth it for some nomads.

These heaters are not designed to be portable. In most cases they should be installed permanently in your vehicle. You can use them portably if your power source is also portable, such as a sufficiently large portable power station, and you can safely vent the exhaust. Some nomads have constructed cases for their heaters to increase portability, or to make it externally mountable.

The smell from spilled diesel fuel is quite persistent. If you can fill your heater's fuel tank outside your vehicle, or can connect your heater directly to your diesel vehicle's fuel tank, you'll avoid this problem.

Changes in elevation can change the effectiveness of diesel heaters (and other fuel-burning heat appliances). If you will spend time at high elevations, be sure that any heater you purchase will perform well. Many heaters have adjustment knobs or other ways to compensate for high elevation.

Safety

You must ventilate diesel heaters to the outside of your vehicle. Because these heaters rely on combustion, we recommend a carbon monoxide detector for safety.

You'll want to keep a few spare parts for your heater in case it malfunctions. It's a good idea to order a spare glow plug/screen and fuel pump. Always have a backup heat source if you are somewhere dangerously cold.

Alternatives

Other available parking heaters are powered by propane or gasoline/petrol. If diesel is available where you live, most nomads find that the advantages usually favor diesel heaters. There are other options for keeping warm.

Installation

Installing a diesel heater requires cutting a hole in your vehicle for the exhaust. If you cannot do that (for example in a removable build vehicle ...

Intake

The intake should be outside the vehicle, drawing in fresh air. An intake inside your living space will create negative air pressure.

If you will use your heater in a dusty area or there will otherwise be a lot of particulate matter in the air (campfire smoke, etc.), you may wish to get a carbon filter to place over the intake. This will prolong the life of your heater.

You may extend the intake hose with another hose if needed. You may wish to use a slightly larger diameter hose.

Diesel fuel tank tapping

If your vehicle's fuel type is diesel, you may be able to tap directly into your fuel tank instead of needing to refill the heater's tank. Your tap should not go all the way to the bottom of your tank; this allows a reserve amount of fuel to be saved for actual driving.

Exhaust

Note that the exhaust hose will be very hot while the heater is in use. Take care to protect yourself and combustible materials near the hose.

The heater's exhaust must slope downward since condensation forms during startup and cooldown. If the exhaust line is horizontal or above, the water cannot drain correctly and will cause problems.

Harvesting the waste heat from exhaust

Exhaust heat capture, by adding a radiator or cooling fins to the exhaust, allows you to recapture some of the heat that is going out the exhaust and would otherwise be wasted to the outdoors. However, this usually hurts more than it helps:

“ Adding a radiator WILL capture more 'lost heat'... but nothing is free! Cooling your exhaust significantly increases the amount of condensation and soot that will collect in your exhaust system, leading to eventual clogs. ... thermal cameras show that 90% of the radiator is doing nothing. If you are hell bent on this issue, just adding some fins to the stock exhaust would be a better bet. You could also just set the output of the heater to 'blow on' the exhaust, and that would work as well, since the exhaust is hotter than the air coming out of the heater. For the ultimate in reliability, especially in extremely cold climates, you should wrap your exhaust in header wrap to keep all the heat in the exhaust until the very tip; this would minimize soot/condensation in the exhaust. This does not capture any lost heat, but it would be ideal for reliability.^[1] ”

“ You might grab a tiny bit of extra heat and it could quiet things down a little, but the downsides are huge. It messes with the combustion and can cause shutdowns, the cooler exhaust makes soot and carbon build up way faster, condensation can cause corrosion, and you’re also increasing the chance of leaks and CO risk. Plus it takes up more space and adds weight, all for almost no real gain since these heaters are already designed to pull most of the usable heat inside. In the end it’s way more hassle than benefit.^[2] ”

Altitude adjustments

For best performance and reliability, you'll want to tune your heater for the altitude you're at. This video demonstrates how to do this.

Brands

Leading brands of diesel heaters include:

• Eberspächer
• Hcalory
• Vevor
• Webasto

Chinese diesel heaters

Derivations and knock-off reproductions of the Webasto and other brands are significantly cheaper than the name brands, and people are generally happy with their performance. Due to the price difference, you'll generally be able to purchase multiple cheap replacements if needed, and still pay less overall. Order a spare glow plug/screen and fuel pump when you purchase your heater.

Maintenance

During the off-season when you aren't regularly using your heater, be sure to run it for about 20 minutes every couple of months to keep things moving. Check your owners manual for additional requirements.

Long term storage

When storing your diesel heater for longer periods:^[3]

1. Drain the fuel completely and ignite the burner until it goes out. (Or run the heater until the tank is empty.)
2. Mix 2 litres (about ½ gallon) of diesel with ¼ litre (about 1 cup) of diesel treatment and add it to the tank.
3. Then ignite burner for 30 seconds, and shut down the unit. Draining the tank again is optional.
4. Disconnect power supply.
5. Consider covering all vents and other openings to prevent insects and other pests from entering, or wrap the whole thing in plastic wrap.

Error codes

• Fault codes for some heaters

Error codes are typically denoted as E-01, E-02, E-03, E-04, E-05, E-06, E-07, E-08, E-09, and E-10. The meanings include electrical faults, motor faults, and fuel problems.

Fuel

In regions where diesel for automotive use is taxed at a different rate or has required additives for emissions reduction, you may be able to purchase cheaper diesel for heating use. In the United States, red diesel can be purchased in agricultural areas where farmers use it to power their vehicles; red diesel cannot be used for on-road driving. In other countries the dye added may be a different color.

Most diesel heaters can be run using alternative fuels like kerosene. However, depending on your heater and the fuel used, this may cause extra soot buildup, or possibly damage your heater or be unsafe. Check your owner's manual or contact the manufacturer.

Resources

• Check out this youtube channel for a very long and detailed breakdown of Chinese diesel heaters, how they work, and how to avoid some of the common pitfalls/failures.
• See this exhaustive playlist about diesel heaters.

Other options