Here I’ll show you step-by-step how I installed a diesel heater in our Jayco Swan camper trailer.

Even though this is one of the 35 Most Popular Jayco Camper Trailer Modifications, it’s safe to say:

The instructions are useless.

So I spent A LOT of time researching how to do this…

(probably more than it took to install it)

…so I’ll also point out some of the dos and don’ts I learned along the way.

Let’s get started with the first step:

1. Buy a diesel heater from eBay

If you’ve already got one, skip this bit and go to Step 2.

But if you haven’t?

Here’s the one I bought:

Our 5KW Diesel Heater from eBay for Our Jayco Swan Camper Trailer

I’m very happy with it!

[Here’s its eBay link… the seller I bought it from has 99% positive feedback]

Yep, they’re affectionately known as ‘Cheap Chinese Diesel Heaters’…

…because they’re much cheaper than the original German versions BUT still consistently get the same good results.

Now, should you buy a 2 kW or a 5 kW diesel heater?

There’s 2 schools of thought here:

  1. Buy the smaller one and work it harder so that it doesn’t get a build-up of carbon, OR
  2. Buy the larger one and don’t work it as hard so there’ll be less wear and tear on the fan and fuel pump (and just run it on high every now and again to burn away the carbon)

The guru of diesel heaters on YouTube (John McK) recommends the latter option…

…and since we’re in a Jayco Swan with a load of canvas, I figure it’s better to err on the side of warmer!

When I bought mine from this eBay seller it arrived in 5 days from Sydney… bargain!

[I added to their 99% positive feedback]

2. Unbox your diesel heater and check if there’s anything else you need for its installation

Like a little boy at Christmas, it was straight onto the kitchen table:

Unboxing Our 5KW Jayco Swan Diesel Heater -Parts and Components

[Natalie wasn’t that impressed]

So what’s the deal with the red circles?

HINT: Make sure you get a diesel heater that comes with a muffler AND an air filter

Some of the diesel heaters are sold with “silencers” that look pretty much like the air filters…

…but bench testing shows they increase the noise!

And they don’t filter. Which makes them useless.

So if you already have your diesel heater BUT it didn’t come with either then this looks like a good combo from eBay

Anyway, here’s the extra bits I bought from Bunnings for our installation:

Tools and Extras Required for Installation of Diesel Heater - Bunnings

My shopping list was:

  • Fielders 100mm Zinc Round Downpipe Pop. To create a turret to neaten up the hole in the floor ($6)
  • Rubber Stopper. This is to help make the fuel pump more quiet ($3)
  • Fire Resistant Silicon Sealant. To form a protective layer between the base plate and the floor ($17) 
  • Craftright 16 Piece Hole Saw Kit. You’ll need a 102 mm and a 76 mm hole… just a decent brand 102 mm hole saw is over $50. So yep, at $20 this cheapo set isn’t great quality, but it’s not like I’ll be using it all the time.

Also:

Double check to make sure you have:

  • 12 small hose clamps, and
  • 4 medium hose clamps

[my kit was short 2 of each so I had to do an extra trip to the local hardware store]

3. Tools used for the diesel heater installation

This is everything I needed:

  • Cordless drill and bits of all sizes
  • Cordless driver and Philips head bit
  • 102 mm hole saw
  • 76 mm hole saw
  • Socket set
  • Spanner set
  • Stanley knife
  • Screwdrivers
  • Caulking gun
  • Hacksaw

Doesn’t look like a lot when it’s in a list… but it sure looked like a lot when I had it everywhere!

4. Find a good spot to put your diesel heater

There’s lots of different places you can put your diesel heater…

For our Jayco Swan (and our preferences) the only logical place seemed to be in the front right corner underneath the couch

Identifying the Ideal Location for the Diesel Heater in Our Jayco Swan

(the aftermarket radio and speakers meant I only had one option for the vent)

Some things to take into consideration when you’re choosing the location of your diesel heater are:

  • What type of Jayco camper trailer layout do you have?
  • What modifications have already been made?
  • Are you willing to lose storage space?
  • How far away is the battery?
  • Where’s a good spot for the fuel can?

And the big one:

  • What’s under the floor?

Before you do anything you’ll need to climb underneath to make sure there’s no chassis, gas pipes, or wiring in the way

5. Mark, measure, and then drill a pilot hole to confirm the exact placement

The planned location for our diesel heater was pretty close to the chassis.

So I put the diesel heater on top of the downpipe pop turret

(so that I could confirm the exact location that the base plate would end up)

Diesel Heater In Position On Turret In Tunnel Boot

Then I took the heater away to leave the turret behind. 

This meant I could drill a small pilot hole: 

Drill Small Pilot Hole In Centre of Turret To Check Fit With Chassis

Spider-Man was glad I checked!

I climbed underneath and placed the centre of the turret over the pilot hole:

It was too close to the chassis by about 30 mm.

To move the diesel heater sideways by that distance would’ve put too much of a bend in the hose…

…so the final position was on an angle. 

Positioning Diesel Heater in Final Position in Jayco Swan - Based on Chassis Location

This picture shows the final position that was determined by both chassis location and vent placement. 

6. Cut a hole in the floor using a hole saw

This was definitely a case of “measure twice, cut once

You don’t need to have a big budget for this:

I used my el cheapo Craftright 102 mm hole saw on my el cheapo Ozito cordless drill:

Using 102 mm Hole Saw to Drill Hole for Diesel Heater

Bunnings’ finest.

And it still did the job perfectly:

Spider-Man Approves of the Hole Saw for Diesel Heater

Spider-Man approves.

HINT: Cut a little from the top, then get underneath and cut from the bottom. You’ll get a MUCH neater hole. 

Testing Downpipe Pop Turret In Hole

[It’s all about preventing water ingress]

7. Outline base plate location and drill holes for securing the diesel heater to the floor

Pretty self explanatory:

Marking Outline And Drill Holes For Bolts For Diesel Heater in Floor of Jayco Swan

8. Add a heat-resistant layer

A few different options here:

  1. Cut a small piece of concrete sheeting
  2. Cut up a heat-proof chopping board, or
  3. Use some fire resistant silicon sealant

I went for the last option to kill two birds with one stone (because I would’ve needed to get some silicon sealant to seal underneath anyway)

Applying Layer of Fire Resistant Sika Silicone Sealant for Diesel Heater Base Plate

Yep, I did fill in all those gaps. That’s a lot of silicon.

9. Connect pipes and hoses to the base of the diesel heater

It’ll make things easier if you connect now

(rather than laying on your back underneath the van)

First, cut the black rubber hose into 6 even pieces

(these are the fuel-line connectors)

Here I’ve connected:

  • Exhaust pipe
  • Air intake hose pipe
  • Fuel line connector

Exhaust Pipe and Air Intake Hose Attached to Base of Diesel Heater

HINT: The fuel line is closest to the cool air intake hose, not the hot exhaust pipe… for obvious reasons

10. Put the diesel heater in position and seal the hole 

Next I stuck the diesel heater in it’s final position…

Seal Hole Underneath Floor When Installing Diesel Heater

…and used the silicone sealant to seal around the turret

11. Mount the exhaust pipe and connect the muffler

Okay, here’s where my initial plan would have let me down…

…I almost made 3 installation mistakes in one go!

First:

See the little hole on the bottom edge of the muffler?

Drainage Weep Hole on Base of Diesel Heater Muffler

It’s a drainage ‘weep’ hole. It’s purpose is to allow water (a byproduce of the diesel heater’s combusion) to escape.

So yeah:

The muffler is mounted vertically, not on it’s side, to allow the water to drain out of the weep hole.

Diesel Heater Muffler Installation - Mounted Vertically Not Horizontally

[I learned that AFTER I’d initially attached it… so I took it off, flattened the bracket, and reattached it]

The good news is when I did this it made it easier for me to avoid another common installation issue:

The exhaust pipe slopes slightly downwards to prevent water from collecting at the low point.  

If there’s a bend in the pipe that’s lower than the exhaust outlet, water will collect there.

Here’s another angle of how it ended up pointing:

Diesel Heater Muffler Exhaust - Pointing Outside of the Van

The exhaust points away from our van. Not under it. 

Now, some might say that these are clean-burning and don’t produce much Carbon Monoxide…

…but all it’d take is for the heater to not be working properly, and next thing you know?

Carbon Monoxide trapped under the van.

No thanks.

12. Mount the air intake hose and connect the air filter

A few simple things here:

I mounted it so that it’s not sucking in the exhaust, and…

Diesel Heater Air Intake Hose and Air Filter

The air filter is facing backwards to avoid high pressure air, dirt, and bugs being pushed into the system when driving.

“And that, Spider-Man, is the heater mounted, exhaust fitted, and air intake sorted”

13. Mark and cut a hole (or holes) for the hot air vent 

In this kit I got a T-Piece and 2 vents…

…but most people only ever install one vent.

So this was pretty simple:

I just traced around the base of the vent with a marker…

Marking The Location of the Diesel Heater Hot Air Outlet Vent in Our Jayco Swan

…then drilled it out using the 76 mm hole saw.

Drill Hole For Diesel Heater Vent 76 mm Hole Saw

If these were the only 2 holes I got out of my Craftright Hole Saw Kit and then they fell apart, I’d still be happy!

14. Screw the hot air vent into its position

Pilot holes. Screws. Simple.

Screw Diesel Heater Hot Air Vent in Position

[my little “helper” is now a Dinosaur]

The vent cover now just snaps onto the base:

Diesel Heater Hot Air Vent Cover Snaps Into Place on Base

Orientated slightly downards, and towards the far end of our Jayco Swan.

15. Join the diesel heater to the vent with the duct pipe 

Duct pipe, a couple of hose clamps, and a screw driver.

Duct Between Diesel Heater and Hot Air Vent

Nothing much can go wrong here

[just remember this will get HOT so it shouldn’t be up against anything]

“And that, T-Rex, is the hot air vent done”

16. Fix the diesel fuel tank with the fittings to connect the fuel line

There was three options for the diesel heater that we bought.

You could either make a hole and insert a nozzle into reinforced sections on the bottom or side of the tank…

Fuel Nozzle Locations On Bottom and Side of Diesel Heater Fuel Tank

…or make a hole in the top and insert the Diesel Heater Fuel Standpipe:

Diesel Heater Fuel Standpipe - Cut to Length

You might’ve noticed that compared to the first photo in this little ‘how to’ I’ve cut the standpipe with my hacksaw to a length where it’s about 50 mm from the bottom with a 45 degree bevel…

…so you can probably guess which option I went for!

Reasons I didn’t got for bottom-mounted are:

  1. Notorious for leaking
  2. Can’t mount the tank with the base resting on anything for additional support
  3. More prone to sediment clogging up fuel lines

Side-mounted? None of those issues.

But you lose about a 1/4 of the tank capacity.

So after a few small holes and a couple of screws:

Diesel Heater Fuel Tank with Standpipe Installed

17. Make and measure a path for the fuel line 

The resting place for our diesel heater fuel tank is in the boot of our Jayco Swan.

There’s already drainage holes in the boot so I didn’t have to drill any holes:

Measuring Length of Fuel Line From Tank to Filter With A Piece of String

I wanted to keep the fuel filter outside because I didn’t like the idea of diesel leaking all through our boot…

…so I used a piece of string to measure the length of the fuel line I needed.

18. Cut the fuel line to length to join the diesel tank to the fuel filter

Using my trusty piece of string, I cut the fuel line on a chopping board using a sharp Stanley Knife

[NOT a pair of scissors or side-cutters because it can compress the narrow diameter fuel line]

Fuel Line Measured and Attached to Diesel Heater Fuel Tank

A couple of things to note here:

  • I’ve used 2 more bits of the black rubber hose that was cut into 6 pieces to act as connectors
  • There’s no gap between the end of the hose and the fuel standpipe nozzzle (pushed tight)
  • I’ve intentionally used the fuel line that it came with

Some people feel the need to upgrade the hard nylon fuel line it comes with to what is used on a car or motorcycle.

If you’re interested there’s a 23 minute video on YouTube just on the fuel delivery system that changed my mind:

I nearly “upgraded” to a fuel hose from SupaCheap Auto… until I learned that the hard nylon narrow-bore fuel line is designed specifically for these systems.

19. Mount the diesel fuel tank

Here I’ve mounted ours in the boot of our Jayco Swan:

It’s dark. Protected from rocks. Free from interference from people.

It’s only mounted using the 3 tech screws and washers in the pre-drilled holes though:

Diesel Heater Fuel Tank Mounted in Boot of Jayco Swan Camper Trailer

Another reason I wanted to make sure that the base of the tank was supported.

I was paranoid that I’d go over a bump and the screws would pull through the tank and it’d fall off

[I haven’t heard of that happening before… but you know, belts-and-braces]

20. Mount the fuel pump (close to the tank)

So I learned that these fuel dosing pumps are more efficient at pushing than they are at sucking…

…so you mount them closer to the fuel tank, not closer to the diesel heater itself.

But they’re also notorious for making a maddening ticking noise.

I came across this great idea of placing a rubber stopper between the Fuel Pump Clip and the chassis:

Diesel Heater Fuel Pump Mounted With Rubber Stopper to Stop Ticking

But also:

The fuel pump is mounted at an angle so the air bubbles created by the pump’s cavitation can escape… if they can’t it messes with the fuel dosage and also creates a metal-on-metal situation.

21. Attach the fuel filter

Remeber:

Unlike a swimming pool filter, diesel fuel filters are designed so that the incoming fuel comes into the outside of the basket.

This is the correct orientation:

Diesel Heater Fuel Filter Connected

Also:

The fuel filter is mounted before the fuel pump

(otherwise the fuel pump will get clogged up)

22. Connect the fuel pump to a primed fuel line

Here I used the piece of string to find the right length to join the fuel pump to the base of the diesel heater

Then, for the final piece of this puzzle:

I cut a piece to join the fuel pump to the fuel filter.

But before I connected the dots, I made sure I primed the fuel line:

Fuel Filter and Fuel Pump for Chinese Diesel Heater

Otherwise:

The poor little fuel pump would have been grinding away, metal on metal, around 15,000 times before it managed to get it’s first sip of diesel

[And if it hadn’t had a meltdown, it’d surely have some arthrits for the future]

So now we have a mounted diesel heater, with vents, and a fully connected fuel system…

23. Connect the wiring harness to the fuel pump

The wiring for these things was the simplest part of the installation:

They are all VERY different connectors so you couldn’t stuff it up if you tried. 

For the wires for the fuel pump I drilled a small hole, popped off the connector, and fed the wires through the hole:

Wiring for Diesel Heater Fuel Pump - Small Hole in Floor

Then re-joined the connector, plugged it in, and neatened everything up with some cable-ties:

Diesel Heater Fuel Pump Wiring Connected Underneath Jayco Swan

24. Mount the Digital Thermostat Controller

Spoiler Alert!

I failed to take a photo on this step… so here’s one that I took AFTER the final step!

This was pretty easy though:

Diesel Heater Digital Thermostat Controller in Jayco Swan Camper Trailer

Join the only 2 connectors that fit each other. 

Screw the back of the controller into the wall.

Hide the wires.

Then…

25. Connect the wiring harness to the battery

This step was simple:

The wiring harness came with a long red wire (that has a fuse in it).

Attach the red wire to the red terminal on the battery.

Then, attach the black wire to the black terminal on the battery.

Once I did that… 

26. Test the diesel heater to make sure it works

I pressed the ‘On’ button, and it worked. Very Well.

I let it run for about 10 minutes on high.

It was very warm.

Good news:

The rubber stopper worked…

…no ticking noise!

How hot does the case of a diesel heater get?

This was the result after 10 minutes on high:

How hot does the case of a diesel heater get

Yes, that’s my comfortably holding my hand on it.

How hot does the base plate of the diesel heater get?

Here’s the meat thermometer again:

How hot does the base plate of a diesel heater get

Definitely warm to touch… but I couldn’t fry an egg on it.

Summary: we’re happy with our Jayco Swan diesel heater installation

We’re happy with our diesel heater…

…it’s definitely going to make life in our Jayco Swan more comfortable this winter!

As I was writing this I said to Natalie:

“This is the article I wish I had when I was installing our diesel heater”

So comment below:

Is there any steps you want more detail on? Anything I’ve missed?

If you’re after one of these diesel heaters, here’s the eBay link to one like we bought

While you’re at it, make sure you get a Carbon Monoxide detector too. We have this one by Quell:

Best Carbon Monoxide Detector for Diesel Heater in Caravan

They’re about $45 from eBay, or just pop down to Bunnings and get one (more like $60 there though)

Otherwise, keep warm, and you might find some other idease here at the 35 Most Popular Jayco Camper Trailer Modifications