Diesel heater in a box

[Howmanygoes]

Been building comfort into the truck so the family will be happier and I can venture out in poorer conditions. First stop was a diesel heater, thanks @Jacob100. Just waiting on the final exhaust section to be delivered so I can fit it and wrap it to finish it off.

I may add an exhaust fan, when I see how much heat is cast off and a USB socket.

Fresh air is drawn in near the air filter.

I wanted everything contained in one box. So the fuel tank is made from a 2L fuel bottle with a vent pipe. It rotates upwards to allow easy filling.

Came out alright for a first effort.

 

[GeekOKent]

That looks amazing. It's a thing on my to-do list as well, get a timer on it and use it to heat the inside of the 105, ready for me to get into!

 

[Dave_S]

How hot does the actual unit get when its running?? I'm maybe being paranoid but I'm not sure about having a plastic fuel tank sat next to the heater... or does it stay pretty cool in there?

Otherwise that looks tidy

 

[Shayne]

Was about to buy a 2kw one the same for my boat after reading 5kw might prove too warm for an under 21ft caravan .

Boats wheelhouse is about 8x4ft .

Youtube shows an obsession with how little diesel they burn over how effective they are so its taken me a while to find this 5kw heating a bus

Skip to 21 minutes to see indoor and outdoor temperature comparison

 

[Towpack]

How hot does the actual unit get when its running?? I'm maybe being paranoid but I'm not sure about having a plastic fuel tank sat next to the heater... or does it stay pretty cool in there?

Otherwise that looks tidy

That was my only reservation. I may be wrong but the heater itself looks like it has part plastic housing. If it has I would imagine it has some heat resisting properties unlike the plastic box.

 

[Shayne]

If its working its sucking cold air and blowing it out through a small heated element i would assume . Most i've seen are mounted on wood .

 

[AndycruiserguyLomas]

dear old Chris made one similar but with the tank on the outside, quite effective but was a bit bigger and more bulky than yours in the box you have.

 

[Howmanygoes]

dear old Chris made one similar but with the tank on the outside, quite effective but was a bit bigger and more bulky than yours in the box you have.

Chris gave me the idea, then Andy showed me his installed one. As I still need all my rear seats, it had to go in a box.

Temp wise HDPE starts to melts about 130dC. The plastic shell gets warm to touch, but so far not hot. The exhaust will be wrapped which should keep the temp down to about 120-150dc the fuel lines would likely melt before the tank.

Once the exhaust arrives and fitted I will see if I can get a laser thermometer to take some readings

 

[guyc]

The chinese heater debate often rages on the self build motorhome forums so it will be interesting to see how you get on.

I've just priced a Webasto one up and it is £1500 although that is to replace the existing chinese one that has given up the ghost.

 

[Jacob100]

Good to see, Chris. Always get satisfaction from passing things on to the forum.

 

[fbnss]

@Rosy made one too

 

[Rosy]

@Howmanygoes looks great. As nick said I built something similar.

A couple of points to consider based on my build:

• Wrap the exhaust - the heat coming off the short section of pipe inside the box was enough to overheat the unit with the lid on. Wrapping it with some of that exhaust fiberglass stuff made all the difference.
• Consider ventilating the box - as the previous point a couple of vent holes to let the box breath also help with cooling. I used some off the shelf 80mm PC vent covers on either side to do this. I even went so far as to add a temperature controller to switch the fans on above a threshold temp but this proved unnecessary.
• Consider air intake hose - you want to create a decent amount of separation between your exhaust and cool air intake. I added a meter of hose to the other side and a vertical "Chimney" to vent the exhaust on the outside of the box.
• Consider a remote controller - mine was a very early knockoff that didnt have this which meant I needed to run another lead to bring the controller inside the tent. Far simpler to mount the main controller in the box and work it via remote.

I like that you've kept the diesel tank in the box - I made a separate attachment to connect it to a 5l can but that's just more to carry. I would take this approach next time as well as possibly adding a small battery so that its fully self contained.

 

[Howmanygoes]

@Rosy, cheers. I looked how you did yours when we went to the meet Jacob set up.

Exhaust is now fitted and wrapped with exhaust bandage. I have lots left so can add extra layers if needed.
I have vent holes, but debating adding an exhausting fan (computer fan) to draw warm air out. I hope I can then keep the lid on, quieting the tick tick of the pump.
Thought about the battery idea too but don't have a lot of room left. I have a remote control.
The heater pulls cold air in from the opposite end to my cold air intake, I have a short section of exhaust which has the silencer fitted which I will fit whilst in use.

Just need to finalise where I will put it when in use. Close to the RTT or on the floor and run a long hose?

 

[Rosy]

Just need to finalise where I will put it when in use. Close to the RTT or on the floor and run a long hose?

yep - that's pretty much it

 

[Lorin]

Here’s mine.

Fully self contained in a tool box. Air is drawn into the box through two vents therefore keeping the heater cool and benefitting from exhaust heat. Fuel tank and box are protected from heat with some fireproof board. There is a controller in the box and also one on an extension that goes in the tent. Full exhaust with silencer is separate and simply push fits on when needed. Exhaust is properly sealed with no risk of fumes going into the box. The fuel tank is vented to the outside to prevent fumes. I did it like this make the unit as water resistant as possible as I keep it outside on the trailer. Hasn’t leaked yet.

 

[Howmanygoes]

Said I would feedback with temperatures etc

Unit was run up to a stable working temperature on level 3 fan. The digital thermometer is not calibrated. The box lid was then placed on and the unit run for an hour. It was overcast and dry. The lid was removed and temperature readings taken.

 

[stumog]

So I acquired a diesel heater this weekend so looking to build a box. I was wondering how you guys decided on the size of the fuel tank? How much do these use per night in your experience approximately only as I under stand so many factors. I suppose I am asking should I go for a 5l tank and 2l tank or a 10l tank

 

[Rosy]

I use a 5L tank which is plenty to run our heater on a medium setting for nearly 2 full days

 

[Howmanygoes]

The 2l tank does a full over night with spare. For me it made the boxed heater easier to load and store as everything was in the one box. I then have a 20l Jerry. Any longer than a couple of days you would need to top up. The alternative could be to hard fix and plumb to your main tank.

 

[stumog]

Thanks chaps will look for a box to take a 5l tank. Haven't got room for a external also. Most stuff we do is weekends