A caravan diesel heater installation is one of the best DIY mods you can make for your caravan, RV, motorhome, camper or bus! These guys go for less than $200 on eBay these days and with this step-by-step process, anyone who’s handy on the tools can have it in before happy hour.
Here we’ll go through the process of choosing which unit you should buy (either an expensive name brand one or a cheap Chinese diesel heater) and what will come included in your installation kit. Another consideration is the 2kW vs 5kW diesel heater, which will be a decision made based on your type of set up.
Once you’ve got your ideal diesel heater unit nailed down, it’s time to go through the step-by-step installation process, which has all been laid out for you here with photos and diagrams along the way.
Let’s get into it!
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Buying a Diesel Heater
For your caravan diesel heater installation, you’re obviously going to need to have your new diesel heater on hand. Have a look through the information below to help you decide which diesel heater is going to best suit your budget and requirements.
Choosing Your Brand of Diesel Heater
There are a handful of established caravan diesel heater brands available, including Webasto and Eberspacher. They’re both high quality companies who’ve built solid reputations for themselves. However, they’re also well-known for being very expensive!
As with all things in this modern age, you can just as easily get a cheap Chinese diesel heater from eBay, which does just as good a job. In fact, these buggers are getting so popular there are even multiple Facebook communities dedicated to installation, troubleshooting and spare parts. Be sure to always read the reviews to feel confident you’re buying from a good seller.
Diesel Heater Price Comparison (AUD):
|2kW||4 – 5kW||Where to Buy|
|CHINESE Diesel Heater||From $138||From $168||eBay →|
|BELIEF Diesel Heater||From $1,150||From $1,310||Caravan RV Camping →|
|AUTOTERM Diesel Heater||From $1,436||–||Caravan RV Camping →|
|WEBASTO Diesel Heater||From $1,720||–||Caravan RV Camping →|
|EBERSPACHER Diesel Heater||From $2,349||From $3,999||Caravan RV Camping →|
Yep, you read that right. The Chinese diesel heaters start from under $200, while the branded ones are well over the $1300 mark.
While some people say, “You get what you pay for,” there are loads of people who swear by their eBay diesel heater. In fact, that’s what we installed and besides an error code that we had to figure out, the thing worked brilliantly.
At the end of the day, the choice is yours. If you’re unsure on which way to go, you could always put the question to the Facebook community members in The OZ BIG LAP Crew and find out what experiences others have had.
A word from the wise about the Chinese diesel heaters off eBay – make sure you go right through the ad and check that it comes with the whole installation kit before purchasing.
2kW vs 5kW Diesel Heater
When looking at a 2kW vs 5kW diesel heater, the prices are much of a muchness in terms of the Chinese diesel heaters. However, if you’re going for a name brand one, the price difference can range from a few hundred dollars right up to a grand!
Deciding on which diesel heater will suit you the best can come down to more than just the price. Here are some considerations to look at when deciding on a 2kW vs 5kW diesel heater for caravan installation.
Size & Style of Van
- For a smaller van, the 2kW will heat up the space with no troubles.
- Older vans with very little insulation will experience greater heat loss, so you may want to consider the larger 5kW unit.
- For larger vans, pop tops, expandas and vans that contain canvas, you’ll be dealing with heat loss at a faster rate, therefore the 5kW can be a better option.
Diesel Heater Unit Size & Weight
Looking at the various diesel heaters available, here are some general measurements that I found (to be used as a guide only). If you’re super tight with space and/ or weight allowances, you might prefer to go for the smallest unit that you can find.
|Size (mm)||2kW Weight||5kW Weight|
|CHINESE Diesel Heater||140 x 140 x 400||7 – 8.5 kg||7 – 8.5 kg|
|BELIEF Diesel Heater||120 x 121 x 323||2.6 kg||4.5 kg|
|AUTOTERM Diesel Heater||119 x 145 x 310||6.5 kg||–|
|WEBASTO Diesel Heater||120 x 120 x 320||2.6 kg||–|
|EBERSPACHER Diesel Heater||140 x 150 x 370||2.7 kg||4.5 kg|
2kW vs 5kW Diesel Heater Running Differences
2kW Diesel Heater
- Less powerful, therefore 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
- Will be run on high, so don’t need to worry about carbon build-up
- Being run on high means you’ll be using more fuel
5kW Diesel Heater:
- Generally only needs to run on low due to its power
- 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
The Climates You Plan on Visiting
A big consideration when installing a diesel heater in a caravan is what parts of the country you plan on travelling through.
If you know you’ll be heading down to Tasmania and across the bottom of Australia in the winter, opting for the 5kW is going to be beneficial for you.
However, if you migrate north in the winter and only need it to take the chill out of the air on cooler nights, the 2kW is going to do the job just fine.
My Personal Experience
We went with the 5kW diesel heater, reasoning that we could easily turn the fan and temperature down if it got too hot.
To be honest, even in a 23 foot caravan, the 5kW heats the space really quickly! In fact, we’d be opening the windows just to let some of the heat out on a night that’s chilly, but not absolutely freezing. That’s what we experienced on cold, outback Queensland nights.
If we found ourselves in the snow in Victoria in the middle of winter, I think every inch of the 5kW heater would be welcome. So, no regrets about the 5kW in a larger van, but I still think the 2kW would be up to the task in most circumstances.
We did have a fuel pump error when we first installed the diesel heater, but the seller was happy enough to send out another one. The only problem was that it was coming from China, which meant we had to wait 3 weeks for it to arrive and we were in the Outback at the time.
But, collecting mail while travelling is easy enough with an Australia Post Parcel Locker number. More on that in the article below.
2kW vs 5kW Diesel Heater Conclusion
When comparing the 2kW vs 5kW diesel heater for caravan installation, the 5kW is great for larger caravans and vans that contain canvas, which will leak out the heat a lot faster. For smaller vans, the 2kW will do the job perfectly and may even take up slightly less space when it comes to installation.
Keep in mind that the 2kW will mostly be run on high (being a smaller unit), therefore it will be noisier and use more fuel. The 5kW will be used on low much of the time, so you’ll need to switch it to high sporadically to burn off any carbon build-up. The 5kW can heat up a space very quickly, which may be too much in a smaller van.
What’s Included with the Diesel Heater?
This is what a general caravan diesel heater installation kit will look like. If you end up purchasing a Chinese diesel heater, make sure you check the fine print and that you’re buying a full kit (not just the tank).
An optional extra with many of the Chinese diesel heaters is a remote control (so you can switch the heater on without having to get out of bed on a frosty morning!). I’d recommend getting one with a remote as they are usually at no extra cost.
However, some of the brand name caravan diesel heaters will hit you up for an extra $150 for the remote, which is something to be aware of.
Caravan Diesel Heater Installation Kit:
- 1x Diesel Heater (2kW or 5kW)
- 1x Air Intake Pipe
- 1x LCD Thermostat
- 1x Silencer (muffler)
- 1x 15L Fuel Tank
- 1x Mounting Plate
- 1x Exhaust Pipe
- 1x Fuel Pump
- 1x Fuel Pump Shock Clip
- 1x Diesel Filter
- 1x Fuel Line
- 1x Wiring Harness
- 1x Remote Control
- 2x Duct
- 2x Vent
- 1x Installation Kit
- 1x Air Filter
- 1x T-piece
Any additional brackets, fuel lines and so on that you require will have to be purchased separately, but you shouldn’t need for much.
Caravan Diesel Heater Installation
▶️ VIDEO: Diesel Heater Install
If you prefer to see things visually, here’s a quick install video where you can pause as you go to follow the steps.
Chinese Diesel Heater Installation Instructions
The above diagram is a good example of Chinese diesel heater installation instructions, just to give you an idea of which pieces connect to what. Note that the fuel pump needs to be on an angle somewhere between 15-30°, but we’ll get to that further below.
Tools and Supplies You’ll Need
For a DIY caravan diesel heater installation, there are few tools and supplies that you’ll need to have on hand:
- Pen (for marking positions)
- Measuring Tape
- Piece of wire (an unbent wire coat hanger will do)
- Cordless Drill & various bits
- Hole Saw or Hack Saw Blade
- Ratchet with extension & 10mm socket
Select a Spot to Install your Diesel Heater
The first step is to figure out the best place to install your diesel heater within the caravan. Generally, the best place for installation is either under the dinette seating or under the bed. You will need a bit of room around the unit for the air intake pipe, so make sure to allow for that.
We decided to put ours under the dinette seat, because we didn’t want other items under the bed to knock the diesel heater in transit. If you are worried about other items moving around against the diesel heater, you could put a timber case around it for protection (although they are solid once mounted).
Does the diesel heater unit get hot?
Although I expected the outside of the diesel heater unit to get a little hot, it actually only gets warm to the touch. You can easily put your hand on the outside of the unit and it’s fine.
So, although you definitely don’t want to install the diesel heater against anything else, you don’t need to stress about it overheating.
Don’t forget to check underneath the van!
Once you’ve found a good spot for the unit inside, go and have a look underneath your van and make sure that you have plenty of space to drill holes etc. You don’t want to be hitting any chassis rails, water tanks or gas lines!
An easy way to check your location is to mark the middle of where you want the base plate to go (inside the van), drill a small pilot hole and leave the drill bit in the hole. Now go and have a look underneath the van, using the protruding drill bit as a guide.
- Position the unit inside the van. Make sure you’ve got enough space between the diesel heater and the cabinet wall for the ducting
- Hold the mounting plate underneath the caravan and make sure you’ve got enough space
Cut a Hole for the Mounting Plate
Once you’ve triple checked your measurements and made sure you’ve found the best spot for your diesel heater (with plenty of clearance), it’s time to move on to the mounting plate.
The next step is to cut a hole in the floor, underneath where the diesel heater is going to sit. This is where the mounting plate will slot down into and the intake and exhaust will feed out of.
Measure the diameter of the circle underneath the mounting plate to check what size hole you’ll need to cut. They generally require around a 100mm hole.
Options for cutting the hole:
- Use a hole saw
- Drill lots of little pilot holes around your circle marking, then use a hacksaw blade to cut out the circle
Attach the Mounting Plate
Once you’ve cut the hole in the caravan floor, put some silicone underneath the mounting plate base and around the hole, then slot it into place. Screw the four corners down so that it’s secure. Now you can mount the diesel heater unit.
NOTE: Before mounting the diesel heater, you can fit all of the pipes and lines to the bottom of it now, rather than having to do it later from underneath the van. To find detailed instructions for each item, scroll further down the post.
Items to be attached underneath the diesel heater (if you wish to do it now):
1. Air Intake Pipe
2. Exhaust Pipe
3. Fuel Line
Install the Air Inlet & Air Outlet Vents
The next step in your caravan diesel heater installation process is to install the cool air inlet vent and the hot air outlet vent.
How to install the air inlet & outlet vents:
- Measure and mark a circle big enough for the ducting to slot through the cabinet from the front of the diesel heater (air outlet)
- Cut the hole using the same method as you used to cut the hole for the mounting plate
- Cut a small piece of the ducting pipe – just enough to go from the diesel heater to hole you’ve just cut
- Attach the ducting to the vent casing, then slot it in the hole and clamp the ducting to the diesel heater
- Screw in the vent casing, then twist on the outside cover
- Repeat the process for the air inlet ducting, which is going to be a lot longer than the outlet one was (as pictured below from the back of the diesel heater)
NOTE: The air inlet and outlet vents must be further than 10cm apart from each other.
Bolt the Diesel Heater to the Floor Underneath the Caravan
Now it’s time to get under your caravan and secure the diesel heater in place from underneath.
There should be four bolts protruding out through the hole from the bottom of the diesel heater. Using a ratchet with extension and a 10mm socket, attach and secure a washer and a nut (provided) to each of the four bolts. This will pull the diesel heater down and secure it to your mounting plate inside the caravan.
Attach the Air Intake Pipe Underneath the Caravan
Now it’s time to attach the Air Filter to the end of the Air Intake Pipe. Then you’ll need to attach the Air Intake Pipe to the bottom of the diesel heater, underneath your caravan.
The correct slot should be the one closest to the Fuel Line outlet. Don’t forget to put a hose clamp around the top of the pipe to secure it in place. Then you can go ahead and use a bracket to hold the length of Air Intake Pipe in place underneath the caravan.
Attaching the Air Intake Pipe:
- Attach Air Filter to the Air Intake Pipe
- Attach Air Intake Pipe to the diesel heater using a clamp
- Secure the pipe up and out of the way underneath the caravan floor using a bracket (make sure it points to the back of the van so it doesn’t fill with dust while travelling)
Attach the Exhaust Pipe & Muffler
Next, you need to clamp the Exhaust Pipe to the diesel heater, then attach the muffler (silencer) to the end of the exhaust pipe. Using the bracket provided, secure the muffler unit underneath your caravan.
Things to keep in mind when mounting the muffler:
- Point it away from your caravan so the fumes don’t get trapped underneath the van
- Don’t point it towards the awning area or you’ll be sucking in exhaust fumes when you sit outside
- Try to run the exhaust pipe on a slight decline from the diesel heater unit (to allow any condensation to drip out)
- Mount the muffler with the screw hole at the top and the condensation drainage hole at the bottom
Mount the Fuel Tank
Where you choose to mount the diesel heater Fuel Tank is entirely up to you. We opted to put it on the back of the van with the other jerry cans. Some people add it to their tool box on the drawbar. Wherever makes the most sense for your set-up is fine.
You’ll need to install the Fuel Line Nipple inside the Fuel Tank, which can be a bit tricky.
There are two options on the Fuel Tank for you to drill out and insert the Fuel Line Nipple. One on the side of the tank and one on the bottom. Be aware that if you go for the side hole, the fuel pump will never be able to access that last bit of fuel in the bottom of the tank.
Choose which one suits you the best, then drill a hole small enough for the Fuel Line Nipple to slot snugly into.
The Fuel Line Nipple will need to be inserted from inside the tank and protrude out the bottom (or side). To do this, grab a long piece of wire (an unbent coat hanger will do) that you can slot the Fuel Line Nipple onto. Then feed that wire through your drilled hole and up through the mouth of the tank. Sit the Fuel Line Nipple on the top end of the wire, then feed the nipple down into the slot.
From there, you can fasten it from the outside with the o-ring and a nut. Next, you can add your fuel line and a piece of black joiner to the nipple and secure it with a clamp.
Setting up the Fuel Tank:
- Drill a hole in the allotted spot either on the side of the Fuel Tank OR the bottom of the tank
- Insert a piece of wire (e.g. unbent wire coat hanger) through the drilled hole and up through the opening at the top of the tank
- Sit the Fuel Line Nipple on the end of the wire up the top, then feed it down into the drilled hole at the bottom
- Secure the nipple in place with an o-ring and nut on the outside of the tank
- Attach the joiner and fuel line, then clamp it in place
If you’re wondering about the legalities around carrying spare fuel on the back of a trailer or caravan, check out the article below.
Mount the Fuel Pump & Fuel Filter
Before mounting the Fuel Filter and the Fuel Pump, you’ll need slide joiners onto each end. These will get clamped on when the fuel line is added. Find a spot underneath the van to mount the filter and pump, closer to the fuel tank end.
NOTE: They say not to put the pump more than 2 metres away from the fuel tank.
Tips for Mounting the Fuel Filter & Fuel Pump:
- Mount the filter and pump somewhere underneath the van, but up near the fuel tank
- The Fuel Filter gets mounted closest to the fuel tank
- The Fuel Pump gets mounted closer to the diesel heater using the Fuel Pump Shock Clip
- Make sure both the filter and the pump are mounted on an angle somewhere between 15 – 30º for optimal functionality
Attach the Fuel Line
Now it’s time to add your fuel line from the tank, to the filter and the pump, then up to the diesel heater.
Measure 3 lengths of Fuel Line:
- From the Fuel Tank to the Fuel Filter
- From the Fuel Filter to the Fuel Pump
- From the Fuel Pump to the Diesel Heater
NOTE: Make sure you use a very sharp blade on a flat surface to cut the fuel line so that you don’t crush it.
When it comes to attaching each length of Fuel Line, you will need to slip a clamp on for each end of the line, so that they’re all secured in place.
If you can pre-prime the Fuel Line from the tank to the Fuel Pump now, you’re going to save some wear and tear on the pump in the initial prime and start-up.
Connect the Wiring & Monitor
The plug-and-play wiring that comes with the diesel heater is really simple to connect. The different shaped connections are self-explanatory and it’s easy to see what goes to what.
The only real knowledge that you’ll require here is the basics of connecting the positive and negative wires to the caravan’s battery power and installing the fuse.
Find a convenient place on the wall to mount the LCD Monitor Display, which is how you’ll be operating your diesel heater once fully installed.
Here are where the different connections go:
- Connection to the Diesel Heater
- Connection to the Fuel Pump
- Connection to the LED Control Panel
- Connect the positive and negative wires to the battery terminals
You may have to drill a few more small holes to run your wiring to the different places (e.g. the Fuel Pump under the van). You should be able to take the connection casings off in order to slip the wiring through a small hole, then connect the wires back up to the casing.
Seal Any Raw Timber Underneath the Van
If any of the timber underneath the van splintered during the hole cutting, make sure you seal it off with a bit of paint. It just helps to keep water and moisture out of the timber flooring.
And that is your caravan diesel heater installation complete! Take a look at the steps below for firing up your Chinese diesel heater (or fancy one, if you went for a brand name) for the first time. Don’t forget to start with priming the fuel pump.
Starting the Caravan Diesel Heater for the First Time
STEP 1: Prime the Fuel Pump
The very first thing you need to do after your caravan diesel heater installation is to prime the fuel pump. Follow the instructions below on how to do that using the control panel.
How to prime a diesel heater fuel pump:
- Hold down 🆗 (OK), then push the 🔽 (down arrow)
- You’ll see ‘H OF’ flashing on the screen
- Push the 🔼 (up arrow)
- Now you’ll see ‘H ON’ flashing on the screen
- You should hear the pump start ticking underneath the van
- Keep priming until the fuel makes it all the way to the diesel heater unit (you can check by having a look at the fuel in the fuel line). You may need to keep turning on the ‘Prime Cycle’ via the monitor as some units will automatically stop priming after 60 seconds.
STEP 2: Turn the Diesel Heater On/ Off
How to turn the diesel heater on:
- Push the ⎋ (power) button
- As the heater gets up to temperature, you’ll notice the lines across the bottom of the ‘diesel heater’ image increase on the screen
You can expect the heater to be smokey the first time you fire it up. Whether it’s burning off excess fuel from over priming or extra oxygen that was sitting in the lines, it’s completely normal.
How to see what voltage the unit is running at (with regards to your battery):
- Click through the 🆗 (OK) button until you get to a number with a little ‘v’ after it
How to see any Error Codes:
- Click through the 🆗 (OK) button until you get to an ‘E.’ If there are any errors, it will show an ‘E’ with a number after it (e.g. E-07)
How to turn the diesel heater off:
- Hold the ⎋ (power) button until the unit switches off
- The heater will now go through a ‘cool down’ cycle
STEP 3: Set the Temperature
How to adjust the diesel heater temperature:
- Push the 🔼 (up arrow) and the ⚙︎ (settings) button at the same time
- Use the 🔼 (up arrow) and 🔽 (down arrow) to increase/ decrease the temperature
How to view the current temperature inside the caravan:
- Push 🆗 (OK) to see the ambient temperature in ºC
- Push 🆗 (OK) again to see what temperature you’ve got the heater set to run at
STEP 4: Set the Clock & Timer
How to set the clock on the diesel heater control panel:
- Push the ⚙︎ (settings) button
- The first number will flash. Use the 🔼 (up arrow) and 🔽 (down arrow) to change the number up or down
- Push 🆗 (OK) to move on to the next number, then use the arrows to set the correct digit
- Push 🆗 (OK) to get to the ‘Timer’ screen
How to set the diesel heater timer:
- If you’ve pushed 🆗 (OK) after setting the time, you’ll now be in the ‘Timer’ screen. If not, push ⚙︎ (settings), then 🆗 (OK) four times to get to the ‘Timer’ screen
- Push 🔼 (up arrow) to turn the timer ‘on’
- Push 🆗 (OK)
- Set your ‘Start Time’ using the up and down arrows, then push 🆗 (OK)
- The next time that shows is the ‘End Time.’ Use the arrows to set the time you want the heater to automatically turn off. Push 🆗 (OK)
- You’ll be taken to a second ‘Timer’ screen, in case you want to add an additional timer. If not, it will bounce back to the original ‘Clock’ screen
STEP 5: Pair the Remote
How to pair the diesel heater remote to the LCD monitor:
- Hold down 🔼 (up arrow) for 5 seconds
- You’ll see ‘HFA’ displayed on the screen
- Press ON on the remote to pair
▶️ VIDEO: Chinese Diesel Heater Settings
Diesel Heater Cheat Sheet
- Complete Error Code List
- 80+ Troubleshooting Tasks
- TICK off tasks as you try them
- RECORD notes
- Printable & Digital
That’s it for the caravan diesel heater installation, now you can enjoy comfortable winter camping! Feel free to share your own tips, hacks and mistakes from your own installation experience, in the comments down below.