Author Topic: Diesel Heaters  (Read 4462 times)

guest22972

  • Guest
Diesel Heaters
« on: July 07, 2019, 11:38:30 AM »

I have seen these small Chinese Diesel heaters available for Caravans and the like and did a bit of a search on them.

https://www.ebay.com.au/itm/Diesel-Air-Heater-12V-8KW-Remote-Control-Convenient-Durable-Adjustable-RV/113743502806?hash=item1a7ba41dd6:g:ILcAAOSwWiJc1OdO

I was wondering about them for running on veg oil and that would be a cheap and safe way to heat the house. With an output of 5 ( or 8 ) Kw, they would put out enough to make a difference.  Looking on the world encyclopedia, Youtoobe, I found a guy that had done some tests on this.  The thing failed to run on 100% New oil but was happy enough on 50%.

I have conversed with him a bit after seeing he had the idea also of heating his home with the thing and asked how it was going longer term and if he was using any veg oil in the thing?  He said he had and it was happy up to 70%. Of course this got the rusty wheels upstairs Grinding.......

Much as I am obsessed with covering the place in solar panels, they have been coming up a LONG way short of late and heating with the Ducted air is costing a fortune in the generation shortfall.  It's pretty clear that no amount of panels is going to be able to keep up with my electrical needs due to heating in winter. Today was pretty clear and even after adding yet more panels to my systems through the week, I made 30 Kwh and used 55 so still a shortfall and I didn't even kick in the hot water in that period.

 Here a Kwh of electricity is .30c.  Diesel Fluctuates but if you call it  $1.40L, that would probably average out.  Diesel has about 10Kw of energy per Litre so that would make 1 Kw about  .14C, Half the cost of electricity.  The heaters have a specified fuel consumption of about 600Ml an hour or I think, about 80% efficiency.... but could be improved.  If we say 8Kwh of DELIVERED heat, that makes it about 17,5 C per KWH.  Still very worth while.

Of course if we can add 50% Free Veg oil, that would make it half so about .9C kwh delivered.  1/3rd the cost of power here which in winter I am paying for.....  Horriffic as that is!
I know prices for fuel and power will vary around the world and we have high power prices so this may not work out economical everywhere.  For us in oz, it looks pretty good though.

These heaters have a room air inlet and outlet and an intake and exhaust for the burner. Obviously the majority of the heat loss is going out the exhaust.  Just like an engine, seems to me that if we can capture this lost heat to whatever degree our efficiency goes up. If a simple Tube in tube heat exchanger was fabricated, the inlet air could be preheated before it went through the heater and a lot of the heat recovered. Should be very easy in a stationary  setup. Another use could be water preheating. Gas heaters just have a flue up the middle so if the heater were suitable located, the exhaust could be directed up the middle of a water heater and the energy recovered that way.  From what I can tell the exhaust is quite hot if not in great volume.
Might be OK to Duct into my greenhouse as well. Co2 and heat. Perfect!  :0)

In any case, with a little DIY ingenuity, Shouldn't be hard to increase efficiency of these things and drop running costs significantly as well.

I have looked at a number of vids on these things and although most tend to be install vids, I haven't found one where anyone is having problems with them as yet which is encouraging.  The longevity does concern me though.
If I am saving 30C ( power) minus 9C (Heater running cost 50% Veg) that's 21C Kwh Saving.  The best price I can find on the units is a tad over $150 which would make the break even ( less stuffing around) cost about 167 KW Hours of run time.  We are heating about 7 hours a day and for the past few days have been running at about 3 Kwh which is a bare minimum in not too cold weather.  Call that 27Kwh day and we get 6  days to break even.

Someone please check my maths. This is sounding one of those too good to be true deals. Must have stuffed up somewhere but I can't find it.

Thinking some more, I can't see there is a lot to go wrong with these things. There is a fan for the room air to be moved through the heater, there may be  a small fan for the burner as well. Neither of these I can see being costly to replace with off the shelf or bodge able components. Fans last forever in computers and cars anyway so probably Low failure risk there.
The only other thing is a solenoid fuel pump which may be a little more tricky as from what I can tell, it is pulsed by the heater controller to meter the fuel. Where a normal solenoid pump oscillates to move the fuel with what is probably an internal make and break, I saw on one vid connecting the power to the pump pulls it in and it stays there until the power is released again.  this may make it a bit specialist ( Re, exy) or it might be possible to hack a regular fuel pump.  On the 3rd hand, even if it is a specific pump, it's Chinese. If it cost $20  delivered, I'd be surprised. 

The rest are electronics which would be subject to infinitely less vibration and physical load than in a Vehicle so again I'd have to put that at low risk.
IF my figures are correct, at $150, one would still be making a good saving even if the thing had to be replaced every winter!

And there is yet another possibility......

Haven't made any in years but when I was, we were knocking out Biodiesel for about .27 C litre.  I have no idea what the cost of meth is these days and I know KOH hasn't gone down but, even if it cost .50C/L now, that would still be cheap AND...... given this is for a burner, no need to do 100% conversion so it would be possible to cut back on the Catalysts and make low conversion Bio and drop the cost yet again.
I was looking at a Bio forum the other day and one of the all time Gurus has shown you don't even need to heat the oil to get a reaction, it just speeds it up.  I could hook a fan motor to a home made stirrer, sit that in the top of the drum with everything it in and let that run a day  in summer where it would be about 50% Plus of temp anyhow, let it settle and then Pull the Bio off the top.  Wouldn't even need to wash it, dry or otherwise.

@ 600Ml Hr@ 5KW output ( can't see the need to turn it down in this place) A drum of a 200L batch would yield  around 170L of low conversion Bio which would equate to 283 Running hours or over a month at 8 hours heating time. At 5kw, might be able to decrease that run time a bit.

This is definitely sounding too good to be true!

Time I got to low conversion bio, would be virtually free to run one of these little diesel heaters.
Any costs and time involved, like before, I'll write off to savings on Gym membership which is a sound investment for me.  ;D

As reluctant as I am to buy anything off the shelf especially when it comes to burners, time I get pumps and hose and other things aside from the freebies I have for the project, buying one of these heaters is not going to cost any more that to build something bigger, uglier and with less safety built in.

Someone shoot some holes in this for me. It's looking far too good to be this easy and worthwhile.  :-\



broncodriver99

  • Sr. Member
  • ****
  • Posts: 319
    • View Profile
Re: Diesel Heaters
« Reply #1 on: July 07, 2019, 11:21:22 PM »
Here is a review done by a fella I follow on youtube. He is pretty entertaining and  a pretty good machinist for being self taught. May give you an idea of what to expect from it.

https://www.youtube.com/watch?v=SsHiX-y9RrI

BruceM

  • Hero Member
  • *****
  • Posts: 2786
    • View Profile
Re: Diesel Heaters
« Reply #2 on: July 07, 2019, 11:42:56 PM »
Something to look into if you get one of these is: how well sealed is the sealed combustion. Often, the "sealed" combustion is a farce and you get some combustion gasses in the heated air. 




ajaffa1

  • Hero Member
  • *****
  • Posts: 1402
    • View Profile
Re: Diesel Heaters
« Reply #3 on: July 16, 2019, 10:13:22 AM »
Very interesting concept, when I was a much younger man every car service place had an oil burning heater that they used in the winter to keep warm. These all ran on waste sump oil that they collected during the summer months.

I`m not sure how well this will work with veg oil, I suspect the unit has some sort of spark igniter which will not work with veg. Perhaps a blend of veg and diesel/kero/RUG would work or alternatively set it up with twin tanks so you start and stop it on a volatile fuel while burning veg in between.

I have serious concerns about a heater that is largely encased in flammable plastic, I would recommend you mount the test unit outside on something that will not catch fire, then use a non flammable materials for the ducting.

I will be very interested to hear your conclusions about these as it is bloody freezing in my shed at this time of year, minus one this morning!

Bob

old seagull man

  • Full Member
  • ***
  • Posts: 122
    • View Profile
Re: Diesel Heaters
« Reply #4 on: July 16, 2019, 12:47:30 PM »
Put me down as interested as well. My container workshop is bloody freezing these mornings. and i do have a bit of fish and chip oil around the place.

ajaffa1

  • Hero Member
  • *****
  • Posts: 1402
    • View Profile
Re: Diesel Heaters
« Reply #5 on: July 16, 2019, 01:47:19 PM »
Hi Glort, it`s nice to have an internet connection again, ours failed about ten days ago. When we reported the problem to our telco, by landline telephone, they diagnosed that we needed to buy a new telephone despite the fact that I was talking to them on our existing phone! F*cking morons finally realized that it wasn`t just our property that had no internet, the whole district was disconnected. Eventually they sent out an engineer to reboot the ADSL router at the local exchange. Guess what, all the locals now have internet again, next time it goes out I`ll just go to the local exchange and kick the door in, turn the router off and restart it, problem solved! It`s not quite that simple, this problem occurs every six months, I suspect the router has a memory cache and error file that builds up until it is full at which point it falls on it`s face. A little routine maintenance and remote supervision would cure the problem but I`d bet my house it will fail again in December or  January. The real killer with these outages is that the local Canoe Center is unable to take bookings or deal with necessary bank transactions, I would estimate the financial loss at between $5,000 and $10,000, none of which the telco is responsible for unless we can prove negligence!

Enough of my problems, back to your project. I have never seen a glow plug that would heat diesel/kero/veg to the point of ignition. Much more likely it heats it to increase volatility before passing it through an atomizer nozzle with a spark igniter. Once alight the fuel burn should be self sustaining. I think I suggested before that a gas pilot light could easily replace the spark igniter and would be better suited to igniting veg oil.

Your concerns about the dangers of mixing diesel/RUG are unfounded. I recently wanted to quench some red hot steel parts in oil, the only oil I had available was a 5% RUG/diesel mix left over from fighting the forest fires earlier this year. I filled a container with the mixture, dropped the red hot steel into it and ran like f*ck. I was expecting it to ignite or worse but nothing happened, it did boil rather harder than neat diesel but left a very nice blued finish on the steel. I continued with this process for over an hour with no ill effects until I managed to boil the Diesel/RUG mix at which point it spilled out of it`s container and all over the shed floor! So much for health and safety.

I like your idea of feeding the hot/return air through a window, I have no idea about which way your windows open but a sliding window could easily be modified with a small strip of plywood to allow for the inlet and outlet pipes, without effecting the window.

With respect to your idea of water injection, I doubt that this will do anything. In an ICE the water droplets work under high pressure on each compression stroke, this has a hydraulic/steam cleaning effect that you will not find in an low pressure burner system but I might be wrong and look forward to hearing what you discover.

Generally you need to adjust the fuel air mixture in any burner until you have no signs of yellow flames; blue is good, yellow/orange produces soot and blocked chimneys and all the associated dangers, carbon monoxide and etc.

Let us all know what you find out.

Bob


EdDee

  • Hero Member
  • *****
  • Posts: 772
    • View Profile
Re: Diesel Heaters
« Reply #6 on: July 16, 2019, 03:24:39 PM »
I jump in to add my not even 1c worth....

<Quote:>
With respect to your idea of water injection, I doubt that this will do anything. In an ICE the water droplets work under high pressure on each compression stroke, this has a hydraulic/steam cleaning effect that you will not find in an low pressure burner system but I might be wrong and look forward to hearing what you discover.
<Unquote>

I have been playing around a little with this lately and found one interesting thing, haven't verified or documented it properly yet, but when I took the water from the over pressure bleed off/expansion valve of my boiler to the path of the flame, the stack cooled slightly overall, but I found the heat transfer to the heatex coil a little better... Could have been atmospherics, dumb luck, or error... As I say, I need to look into this a bit more, it could prove interesting....

Cheers
Ed
12/1 750RPM/9HP Roid 5kVA- WMO Disposal/Electricity & Hot Water Gen
12/1 650RPM/8HP Roid 4.5kVa - Demon Dino
Chinese Yanmar - Silent Runner with AutoStart
Classic Komatsu 1963 Dozer/Fergusson 35 Gold Belly ...
Bikes,Cars,Gunsmithing & Paintball...Oh yes, a 5Ha open air Workshop to play in!

veggie

  • Keep Calm and Start the Lister !
  • Hero Member
  • *****
  • Posts: 610
    • View Profile
Re: Diesel Heaters
« Reply #7 on: August 14, 2019, 05:26:37 PM »

Very interesting little heaters.
So many uses.
Small shop, Greenhouse, Camping vehicle, Generator shed.
- 6/1 GM90 Listeroid - Delco 33si Alternator
- Changfa R175 - Lease/Neville Alternator
- JiangDong R165 Air cooled - 2 kw

veggie

  • Keep Calm and Start the Lister !
  • Hero Member
  • *****
  • Posts: 610
    • View Profile
Re: Diesel Heaters
« Reply #8 on: October 04, 2019, 08:08:35 PM »
Apparently they can run on vegetable oil if diluted with diesel...
https://www.youtube.com/watch?v=-bmELZaH6zQ

Perhaps the ideal situation would be a pure diesel tank for starting and stopping.
A second tank of 50/50% to run on once the heater is hot.
Just like and automobile WVO system.
- 6/1 GM90 Listeroid - Delco 33si Alternator
- Changfa R175 - Lease/Neville Alternator
- JiangDong R165 Air cooled - 2 kw

Desiel

  • Newbie
  • *
  • Posts: 4
    • View Profile
Re: Diesel Heaters
« Reply #9 on: October 29, 2019, 04:48:21 PM »
Hey Glort, I own 2 of these heaters from China, one is in my 1974 vw bus Westphalia, the other heats my backyard mancave (12 by12 1.5 story building), the one in the bus runs about 30 hours a year (winter camping), the one in my man cave runs about 3 hours a night, every night in the winter.I have had 2 failures, the first was the cheapo thermostats that come with them, once I switched over to the simple one knob thermostats, that problem disappeared, the other problem was with carbon. You must turn them to full blast 15 minutes before turning them off, otherwise carbon will build up over time causing smokey exhaust and eventual no start situation there is no spark plugs in these heaters  only a single glow plug that operates at start up, once the combustion chamber comes up to temp, the combustion becomes self sustaining.No fears of exhaust gas leaking into the room air. The way they are constructed and the extremely small amount of fuel precludes that assumption.Feel free to PM me if you have any questions or need advice on installation or operation.

dax021

  • Full Member
  • ***
  • Posts: 164
    • View Profile
Re: Diesel Heaters
« Reply #10 on: October 29, 2019, 06:35:36 PM »
Hey Desiel, I'd like to see a picture of your bus.  Had a 74 myself, although not a Westaphalia, just a panel van (as we called them, no windows).  Turned it into a camper myself.  loved that bus, but hectic on gas.  It was a 2Lt air cooled (originally 1800 cc)

Desiel

  • Newbie
  • *
  • Posts: 4
    • View Profile
Re: Diesel Heaters
« Reply #11 on: October 30, 2019, 04:22:28 PM »
I am at work now, will upload pics of my Westy probably this weekend.I bought my Westy July 2000, drove it one year with that miserable 54 hp engine, could not take it so I installed a 1966 Chevy Corvair 110 along with a 1965 Corvair 4 speed into it (I am a Master A.S.E. mechanic by trade  have since put over 350,000 miles on it.

mikenash

  • Hero Member
  • *****
  • Posts: 792
    • View Profile
Re: Diesel Heaters
« Reply #12 on: October 30, 2019, 05:06:03 PM »
Interesting

For many years I had VWs - owned maybe eight or ten in the years before we had cheap Japanese cars available here.  My ex-wife wrote off at least four of them . . .

The last was a '70 bus with a 3-litre V6 Ford Capri engine which fitted in the hole in the back just nicely

Great to drive, but when it finally did what every Ford V6 engine does and expired in a cloud of expensive oily steam I bought a Toyota and have continued to do so

350,000 miles is impresive

dax021

  • Full Member
  • ***
  • Posts: 164
    • View Profile
Re: Diesel Heaters
« Reply #13 on: November 03, 2019, 12:09:18 PM »
Ford V6 was a common conversion on the old Kombi's here in S. Africa too.  I eventually went another route and installed a Toyota 2CT in mine.  Went better for cheaper than ever before in it's life.  Gave it to my brother around this time and as far as I know it ended up rotting away in a field somewhere.  Pissed off doesn't come close.

mikenash

  • Hero Member
  • *****
  • Posts: 792
    • View Profile
Re: Diesel Heaters
« Reply #14 on: November 04, 2019, 07:27:41 AM »

That would have been a Brilliant Conversion!
Shame your brother didn't appreciate it.  Must have taken some doing to get that configuration Motor  in there!

I had a google and of course there are some vids.  They fit in the hole really well!  And it's an older Toyota (read bullet-proof if you maintain it) with good low-RPM torque.  What a good conversion!

Beats hell out of the just-waiting-to-explode Ford V6.  Only good thing about that was the acceleration from the combination of the low final drive ratio and the 90-odd HP