What Size Diesel Heater for Caravan or Camper?

🔥 2kW vs 5kW Diesel Heater for Caravan (which size?)

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When people think of travelling Australia in a camper or caravan, they generally think of hot temperatures. However, the reality is that many parts of Australia can get bitterly cold, particularly once that suns start to descend below the trees in winter.

A diesel heater is the perfect solution for keeping warm while camping off-grid around Australia.

If you’re deciding what size diesel heater for your caravan a handy way to figure it out is by looking at the length of your van. If you have a smaller van (under 21 foot), the 2kW diesel heater will suit you perfectly, while the 5kW diesel heater is better for caravans over 24 ft long.

In my experience, there are two great ways to keep your caravan or camper toasty in the winter:

  1. Switch the air conditioning unit onto hot – but this will only work when you’re hooked up to 240 volt power.
  2. The more versatile way to heat the van is with a diesel heater. It will run off your solar powered battery set-up and a small tank of diesel.

There are many factors to consider when choosing the right diesel heater for your needs. Let’s explore further.

11 Best Diesel Heaters →
Diesel Heater Install [12 Steps] →
Chinese Heater Troubleshooting →
Chinese Heater Instructions →

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How Does a Diesel Heater Work?

A diesel heater is an encased plastic unit, which is mounted inside of your caravan or camper and produces hot air. A common place to house the diesel heater unit is generally under the bed or under the dinette seating, so that it’s out of the way.

One end of the unit will have an intake pipe, which draws in cold air. The air then passes through the combustion chamber, which heats the air. Lastly, that hot air will be pushed out the other end of the unit with a fan, which blows out into the caravan and heats up your space.

Caravan Diesel Heater
Caravan Diesel Heater

The diesel heater is powered by your 12 volt battery and also connects up to a small diesel tank, which sits either on the back of your caravan or in the front boot.

Installing a diesel heater is a fairly simple process for anyone who’s handy on the tools. If you’re keen on doing on your own install, check out the 12 step process below.

DIY Diesel Heater Install →
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2kw vs 5kw Diesel Heater

2kW vs 5kW Diesel Heater

When it comes to diesel heaters in Australia, the most common sizes to choose from are the 2kW, 2.2kW and 5kW. There are also 8kW units on the market, but they are just way too big for the size of a caravan or camper, so cross them off the list.

In order to keep things simple and help you come to a decision, we will be comparing the 2kW vs 5kW diesel heater units. There are many factors to take into consideration when deciding which heater will be the best unit for you.

2kW vs 5kW Factors to consider:

  • Price
  • Caravan size & style
  • Heater size & weight
  • Running differences
  • Climate

2kW vs 5kW – PRICE

Looking at the table below, you can see how much the prices vary between caravan diesel heaters.

The eBay Chinese heaters are by far the most affordable and they work brilliantly (that’s what we had in our van). For this budget variety, there’s rarely much price difference between the 2kW vs 5kW diesel heaters.

2kW4-5kWWhere to Buy
CHINESE Diesel HeaterFrom $138From $168eBay →
BELIEF Diesel HeaterFrom $1,150From $1,310Caravan RV Camping →
AUTOTERM Diesel HeaterFrom $1,436Caravan RV Camping →
WEBASTO Diesel HeaterFrom $1,720Caravan RV Camping →
EBERSPACHER Diesel HeaterFrom $2,349From $3,999Caravan RV Camping →

While it can sometimes be true in that you get what you pay for, it all depends on whether you want to stick to a smaller budget and go for the Chinese option, or outlay more but have a reputable brand with a solid warranty behind you.

But the fact is, you can buy over 10 Chinese diesel heaters for every 1 Eberspacher!

It’s important to keep in mind that the Chinese diesel heaters are known to throw error codes here and there. Given that there is no after-care with an eBay purchase, you’re largely left on your own when it comes to solving the problem.

If you do go for the Chinese heater and have any issues, be sure to check out the article below covering common Chinese diesel heater problems.

Note – when buying diesel heaters off eBay be sure to read the fine print and make sure you’re getting the entire installation kit.

Chinese Diesel Heater Troubleshooting →


Caravan Diesel Heater LCD Monitor
Diesel heater control pad

The size and style of your caravan is largely the biggest determining factor with a 2kW vs 5kW diesel heater.

SMALLER CARAVANS (under 21ft):

For smaller vans a 2kW diesel heater is perfect.

You can heat the space effectively, but you may need to run the heater on high to keep maintaining the temperature.

At the opposite end of the stick, to have a 5kW heater in a smaller van is going to see you constantly turning the thing on and off because it just keeps getting way too hot!

LARGER CARAVANS (over 21ft):

If your caravan or camper is 21ft or longer, you’ll find that the 5kW is going to heat the space quickly and efficiently, while being able to maintain the temperature on a lower setting.

Having a 2kW heater in a larger van equates to needing to run the heater for longer periods of time in order to remain cosy. Running the heater for longer means that you’re burning through more diesel, plus you’ll be generating noise far longer than if you had a capable 5kW heater.


Another important factor to consider is for those with pop-tops and expanders.

Any van with canvas sections will naturally experience heat loss at a faster rate through the fabric and seams. For smaller vans, which pop up and out, it would be wise to look at the size of your camper once it’s all fully opened up. You may need to consider the 5kw diesel heater so that you’re not having a constant battle to keep the space warm.

Many of the older vans have a limited amount of insulation compared to modern vans. Much like canvas, a lack of insulation will also see a quicker rate of heat loss, so in this case you may want to consider the 5kW system, depending on your length of van.

Diesel heater size in relation to the size and style of your caravan:

Caravan Length & StyleDiesel Heater Size
Under 21 feet2 kW
21 to 24 feet2.2 kW
Over 24 feet5 kW
* Caravans with lots of canvasConsider 5 kW
* Older caravans with little insulationConsider 5 kW
* Colder climatesGo for the 5 kW


The diesel heater size and weight may or may not be a consideration factor for you.

If you’re cutting every corner to keep your caravan weights down, then an extra 4kg in a diesel heater could very well be a huge deal (I get it!). Or maybe you’ve only got a very limited space to install the unit into, so the smallest heater wins the day.

Either way, here are some diesel heater size and weight stats to help you out with your decision.

2 kW Size (mm)2kW Weight5kW Weight
CHINESE Diesel Heater140 x 140 x 4007 – 8.5 kg7 – 8.5 kg
BELIEF Diesel Heater120 x 121 x 3232.6 kg4.5 kg
AUTOTERM Diesel Heater119 x 145 x 3106.5 kg
WEBASTO Diesel Heater120 x 120 x 3202.6 kg
EBERSPACHER Diesel Heater140 x 150 x 3702.7 kg4.5 kg


There’s no doubt about it, the 2kW diesel heater is less powerful than the 5kW. But, bigger is not always better… unless that’s what will work best for your set up.

Something to note with diesel heaters is that if they are run on low all the time, they will end up with a build-up of carbon. For instance, if you were to choose the 5kW heater for a smaller space and found that you never needed to turn it up, you will still need to occasionally run it on high to burn off any build-up.

Below are some 2kW vs 5kW running differences worth considering.

2kW Diesel Heater✔️ For smaller vans
✔️ More comfortable temperature
✔️ Will run on high, so won’t get carbon build-up
❌ Less powerful than 5kW
❌ Longer periods of being on high = noisy
❌ Needs to run longer to achieve same results as the 5kW
❌ Running on high more often means higher diesel usage
5kW Diesel Heater✔️ For larger vans
✔️ Mainly only needs to run on low
✔️ Running on low = less fuel & less noise
✔️ Ability for high heat in sub-zero temps
❌ Sometimes too hot for small spaces
❌ Harder to maintain even temperature
❌ Needs occasional carbon burn-off

2kW Diesel Heater:

  • Less powerful than the 5kW
  • Better for smaller caravans and campers
  • Will need to be run longer to achieve the same results as the 5kW could in a shorter length of time
  • Much more comfortable temperature than the high, fast heat of the 5kW
  • Easier to maintain an even heat
  • Will be run on high, so don’t need to worry about carbon build-up
  • Running it on high means you’ll go through more diesel

5kW Diesel Heater:

  • Generally only needs to run on low due to its power
  • Harder to maintain a comfortable temperature because its sometimes too powerful for small spaces
  • Will still need to be run on high occasionally to burn off the carbon build-up
  • Running it on low means less fuel being used and less noise in the campground
  • Have the option to really crank it up in sub-zero temperatures

2kW vs 5kW – CLIMATE

The last thing to consider when comparing the 2kW vs 5kW diesel heater are the climates and regions you plan on travelling through in your caravan or camper.

If you live in Queensland and mostly plan on using the van for holidays and long weekends all within the state, you might find that the 2kW heater is perfect. You really just want something to take the chill out of the air during winter or if you head west.

Maybe you use your van to migrate north every winter to warmer pastures and don’t need anything too strenuous. Again, the 2kW could be just what you’re looking for.

Alternatively, if you want to take your van all over the Australia including Victoria’s High Country, Tasmania and the Red Centre, you will use every inch of the 5kW system!

For those who live in colder countries, I wouldn’t bother with the 2kW, it probably won’t ever cut the mustard. Go straight for the 5kW.

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What Size Diesel Heater for a Caravan?

There are many factors to consider when deciding what size diesel heater for a caravan or camper is going to suit you the best. The size of your van, plus the addition of any canvas are the two biggest factors.

Use the decision tree below to help you figure out which diesel heater is the best for you.

Which Size Diesel Heater? Decision Tree
[Decision Tree] What size diesel heater for caravan?

When deciding on the 2kW vs 5kW diesel heater for a caravan or camper, the 5kW is perfect for larger caravans and vans that contain canvas, which will leak the heat out faster. For smaller vans, the 2kW will do the job well and will be easier to maintain a steady heat.

Bear in mind that the 2kW will mostly be run on high much of the time, therefore it will be noisier and use more fuel. The 5kW will be used on low majority of the time, so you’ll need to run it on high occasionally to burn off any carbon build-up.

The 5kW will heat up a space very quickly, which may be too much in a smaller van unless you’re often in freezing climates and/ or have lots of heat escaping through the canvas or poor insulation.

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Diesel Heater Cheat Sheet

Diesel Heater Cheat Sheet
  • 12-pages
  • Complete Error Code List
  • 80+ Troubleshooting Tasks
  • TICK off tasks as you try them
  • RECORD notes
  • Printable & Digital
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Diesel Heater Safety

Diesel heaters are extremely safe to run. In fact, the heater unit, which sits inside the caravan or camper should only ever get warm to the touch. You won’t have to worry about the safety of items sitting too close to the unit due to excessive heat.

With a properly installed diesel heater, you shouldn’t be getting any diesel fumes inside the caravan. However, if you do notice a slight fumey smell, it’s most likely due to the wind changing outside and pushing the external exhaust fumes into one of your caravan vents.

Carbon Monoxide Detector

Carbon Monoxide Detector (eBay) →

While carbon monoxide poisoning isn’t an issue with the use of diesel heaters, it’s always recommended to have a carbon monoxide alarm installed in your caravan. Carbon monoxide poisoning occurs when there is too much carbon monoxide in the air, which can happen in closed up caravans that don’t have adequate ventilation.

Always keep the standard air vents in the caravan clear and open as they do a necessary job. Even though it can be tempting to cover up the vents when it’s really cold outside, that ventilation is vital to the air health inside the caravan.

Now you’ve figured out what size diesel heater will suit your caravan or camper, you can be toasty and warm this winter!

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2 thoughts on “🔥 2kW vs 5kW Diesel Heater for Caravan (which size?)”

  1. I severely regret only getting a 2kw heater based on this advice. Even in a van, it’s just not enough. I think the problem is I don’t live in Australia which I now see the author does.

    1. Ahh damn, I’m so sorry. I have mentioned throughout the article that if you live in colder climates, it’s best to go for the larger heater. However, I’ve just added that info into a few more places for those who aren’t from Australia.

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