Webasto/Eberspacher style diesel heater

[Tubetec]

As I mentioned recently I'm searching out low cost means of heating my new home , which I'm currently renovating .
Theres a million knock off Chinese versions of these heaters out there ,
Most are air heaters , they can use as little as 100ml of fuel per hour (for 1kw output)
,to around 450ml per hour @5kw output .

I was able to find a Webasto water heater out of a BMW X5 for less than 100 euros ,
The standard Webasto control panel/timer should work with it .
Some of the heaters come in a metal box with the fuel tank built in ,
I'd avoid the one with the built in tank , its a bit dangerous to have a fuel tank right above the heater itself , users have also reported a strong smell of diesel in the hot air after refueling as any drips or spills end up falling onto the heater itself .
I'll use a 12L outboard motor marine fuel container with the usual priming bulb and quick connect line , that way I can grab the container and hop over the road to the petrol station to fill up , any spills are minimised and the fuel tank can be placed away from the heater unit itself . There have been a few cases where peoples boats have burnt down after a China heater either malfunctioned or was badly installed .
The beauty of it is fuel is available from any garage or forecourt in small quantities and it will also burn various waste oils mixed with diesel or kerosene .
Its also such a simple machine it very easy to service , only moving parts are the fan/motor and fuel pump ,which themselves are very reliable components .
I will also suplement this system with an old fashioned wood burning stove centrally in the property , where air convection will allow heat reach upstairs , Its only in the depths of winter would I need the suplementary diesel heating .

The Webasto thermo top C(water) retails at around 900 euros but they can be had from a car scrap yard for around 100 , that saving will pay for the first few years useage .It consumes around 100w initially to heat the glow plug , then it drops back to around 40W to run the fan and fuel pump , but thats a tiny amount of electrical power relative to the heat output of the unit .

Its a testament to German engineering that the design is basically unchanged since its inception back in the early 1900's , great ideas stand the test of time .
https://eur.vevor.com/diesel-heater-c_10321This company has a variety of models , including the downright dangerous and smelly ones with the fuel tank sitting right on top of the heater .
Below is the thermo top C in a marine setup , I can easily handle the installation and servicing myself ,so no need to call in professionals ,ever .

 

[AnalogPackrat]

Interesting. Never heard of these things. I hope you're keeping the combustion outdoors.

 

[Tubetec]

In a boat or truck the fumes and any condensation are dispersed without an issue ,
In a domestic environment proper handling of the exhaust gases and the noise are an important factor . I havent set this thing up yet , Im still at the design stage for now .

What Im planning to do is this , installing a metal down pipe and guttering for rain water run off from the roof of the property ,instead of the usual plastic .
Then I'll run the exhaust flue within the the drain pipe right upto the roof line , where it vents ,
One issue will be condensation within the exhaust pipe itself , that will cause water too accumulate which if it isnt dealt with will cause a problem . The burner itself will be mounted about 6 feet off the ground out of doors , I'll arrange a purge valve at ground level so any accumulated moisture in the exhaust system can be safely vented to the wastewater pipe and away . The burner will live in an insulated GRP utillity box up on a wall . I'll probably try and arrange it so the intake to the burner functions as air extraction for the bathroom which is adjacent , now any nasty 'niffs from the 'bog' are sent directly for incineration which is an extra bonus .

With energy prices skyrocketing many older people in larger properties are facing stark choices ,
heat or eat ,
There forced to pay extortionate rates from the utillity companies , these simple cheap machines could allow many have their cake and eat it , rather than perish with hunger or die of the cold . A weekly trip to the petrol station with the gerry can might be all thats needed ,at todays forcourt prices it translates into 1/3 the cost of electricity or gas per kwh for the purposes of heating , used cooking oil added to the mix makes further savings to the cost from a waste product . Bio diesel might offer a more sustainable alternative .

The Thermo top C can easily run with an emersion style water tank in the circuit instead of a car engine cooling system ,
A cuppord in the jax can house it , an expansion tank and any other pipework or fittings ,
With a solar panel and 12v lead acid battery to run the heater even if the electricty grid is down we still have heat at the touch of a button or on a timer .
Some guys have created a dual fuel system , it starts up on pure diesel then switches to a mix once the unit is fired up , again at shut down again the unit is run on pure diesel to burn off any residue .

The control unit allows you tweak the parameters of the burner , fuel pump pulse rate is set in Hz ,
then fan RPM controls your air supply , some of the aftermarket controllers even have a phone app which allows you monitor fuel usage ,power ouput , exhaust gas temp , air temp maybe even an oxygen sensor in the exhaust to check all is well .

Anyways I have work for the forseable future as a project manager ,builder ,plumber ,muck shoveler painter and decorator , luckily many of my friends did their time in the building trade so hopefuly a few helping hands along the way , I'll bribe them with beer and a barbeque after .

Gotta head down the town now , I have a to-do list to get through ,

 

[AnalogPackrat]

Does it have induced draft (assuming not)? Pulling combustion air from inside may cause trouble if your home is "tight." If it's drafty, you'll be pulling in cold outside air to replace combustion air.

If you could route part of the flue through the interior of your house you gain some additional heat (and maybe partially mitigate the condensation problem). Probably need some kind of drain arrangement at lowest point of exhaust to allow condensation to exit.

Are you running this to a small radiator or just a fan blowing over the coils?

 

[JohnRoberts]

are these somehow more efficient or just inexpensive? I had an old neighbor (now RIP) who used a wood burning heater located about 50 feet from his house. He eventually couldn't keep up with feeding wood into it, as his age caught up with him.

I feel like my investment into a Mitsubishi heat pump (without any government assistance) has probably paid for itself by now. My unit is marginally sized for my entire house but happy most of the time in my moderate climate. One of the few good things about living in the south.

JR

 

[Tubetec]

I was able to find a UK based company that does a nice exhaust system for the Webasto ,
Its made of 1.5mm stainless steel with a proper muffler and various extra sections depending on whats needed . Theres other places selling similar stuff for twice and three times the price .
https://www.southernmarineproducts.uk/collections/all
These heaters all contain a sintered metal gauze , the fuel and air is blown through this mesh . it tends to become clogged with carbon over time ,
On the thermo top C the burner and gauze come as one part, costing around 300 euros each time it needs to be serviced , its a bit crazy as its only the gauze that wears out , its quite easy to modify the burner and make the gauze replacable which only costs 10 euros , now service costs are practically irrelevent .

 

[JohnRoberts]

Is that mesh like a catalytic convertor?

JR

 

[Tubetec]

The mesh helps hold the heat after the glow plug is off , the fuel is squirted through the mesh and the fan forces air through the slots .
Heres an article about replacing the mesh on the thermo top C ,
https://www.experimental-engineering.co.uk/2020/03/10/webasto-thermo-top-c-burner-mesh-replacement/The guy is rightly anoyed at having to hand over a few hundred pounds each time the gauze wears out ,its very easy to make it field replaceable and the burner housing itself lasts for many years .

 

[Tubetec]

A catalytic convertor isnt appropriate for diesel power , a diesel particulate filter is whats used on modern vehicles to scrub out the dirt .
I had a look and DPF's arent really made for smaller engines , there are a few automotive DPF's for smaller diesel cars of around 1.3-1.5L(70-90kw) ,there still way to big for use with a 5kW heater .
In any case a diesel burner isnt like a combustion engine in that you set your fuel pump and air flow to the required setting and it stays there , not like an engine where the Rpm/output/polution varies depending on driving conditions .
Anyhow my green credentials are impecable , Ive never owned a vehicle , I quit air travel over 20 years ago and as I walk its mostly shoe leather that I've consumed .

A liter of diesel roughly equates to 10kwh , the Webasto produces around 5kw and consumes around .5L per hour , the effeciency of diesel to produce BHP at the wheels in a car is very much lower ,somewhere in the region of 25-30% at best . The Webasto looks to have efficiencies in the high 90's % , better than a solid fuel burning stove ,which can get upto around 85% effecient . Either option beats an open fire by a big margin .

For me the diesel heater makes tons of sense ,
1. I dont need to pay extortionate rates for electric or gas powered heating (40 cent per kwh )
2. I dont need to pay for smokeless coal ,which is a scam , it doesnt burn well and its known those products are bulked out with grit dust dirt and moisture to bring the weight up and in turn means you have nasty ash to pay for disposal of after the flame has died out
3. I dont need an account with an energy provider to faccilitate them ripping me off ,
4. I can buy in fuel as required from any garage/forecourt and blend in other used cooking oils etc to save even more money .

Waste oils can be had for next to nothing , but the enviromental impact of of their production appears worse than fossil fuels , stands to reason really , the earth produced fossil fuels over tens of thousands of years , the only cost is getting it out of the ground .
Diesel costs around 1.50 euro a litre here , kerosene home heating oil is around 1.10 .
either will work fine in the webasto .
Instead of going to the trouble of mixing fuels with used oil it might be easier just to install two fuel pumps , one pure kero or diesel the other for used cooking oil , the system can be started up on diesel , then set to a 1:3 ratio of fuel to waste oils , then back to pure petroleum fuel again before shutdown . Roughly equates to 7 cent per kwh , even an air to water heat exchange costs 10 cent per kwh to run , not to mention the initial installation cost .

 

[JohnRoberts]

I am pleased that the recent notice from my electric utility says that I used 11% less electricity than "efficient" homes near me, closer to half of similar inefficient homes.

I likes my Mitsubishi heat pump.

JR

 

[Tubetec]

A buddy of mine went to town on an underfloor heating system with solar and air to water heat exchange , it works very well but he said he'll be paying back for it till he's 70 ,
I must ask him how its working out in terms of his electricity bills ,

The Webasto arrived , packed in a box along with the X5 fuel filter system , full of juice ,
luckily the postman kept the package the right way up and it didnt spill all over the carpet , I'd have been hung drawn and quartered by 'er indoors if it had

Messrs. BMW saw fit to add a floating mount system to keep any acoustic noise being transferred through the chassis into the cabin , everything sits on big robust vibration damping rubber grommets ,
The entire coolling system opperates at 2.5 bar , the main engine driven water pump doing most of the work .
The off the shelf thermo top C includes an auxilliary plastic electric water pump on the cold side of the circuit , its probably not upto the job of running the show in a domestic environment like I want to do . I'll replace it with a much bigger 12V coollant pump from Pierburg ,its a common part in many of the bigger BMW ,Audi/Volks and Merc models .

This heater needs to be force fed, under pressure , otherwise the water will boil and the heater housing could overheat and crack . Webasto themselves provide a PC based diagnostic software that monitors all the sensors in the burner and in conjunction with flue gas analysis can be used to trim the air/fuel mix for best burn .

Theres a big furore here just now about reliance on fossil fuels , kiss my ass minister, the webasto can run off anything ,
Dual fueling can make use of any waste domestic cooking oil or whats they term bio diesel , which in reality is ordinary diesel with a % of either animal tallow or surplus/used veg oil which has been processed and mixed in , I have to say after looking over the subject the whole basis of of the bio fuel idea is flawed if the cost of production from an agricultural perspective is taken into account , it puts the energy industry in direct competition with food production .

The EU has just announced its latest raft of environmental legislation , I havent had a chance to fully scrutinse yet ,but it looks like strict new limits on the ways and means people use to heat their domestic property are on the way in , stoves and burners of one kind or another are destined to be phased out,
In reality it will be weighted in favour of the utillity companies , people are being sucked dry as it is , dont expect that to end anytime soon ,

As I said Ive never run a vehicle in my life , my Co2 output as an individual is drastically smaller than the average in the western world and some busybody from Europe is going to try and tell me I cant burn a few cups of diesel , very effeciently to heat my home on a winters night .....
Smell the finger Ursula,

 

[Tubetec]

Just as well I kept this thread brewery bound ,
I was always going to veer off into the swamp sooner or later ,
Hows about a group vote on a middle finger emoji in the panel ?
Im already a little too edgy for coffee this morning after attending a gig
in the pub last night , hair of dog is still half a day away .

This energy crisis is being exlpoited to undermine peoples wealth and extract back monnies to ECB coffers , its linked to the banking bailout deal ,
Im folding out of this crap game permanently ,

Dipping truck and car tanks/ injectors at the side of the road is the business of customs and excise/revenue , if they think they can police what people use as fuel in their home in the wilds of Ireland there gonna need reinforcements .

 

[fazer]

Do you guys watch Clarkson‘s Farm? In season two he tries to build a restaurant on the farm and make it into a business by producing all of the food or using farmers in the area to supply food for his restaurant but council hate the idea and basically Nix it. Which reminds me of all the people thinking they’re doing good with Not in my back yard and using their ability to destroy the farmers living while living on a pension. We’ll use solar or wind power and save the planet. Never mind the clouds/fog get in the way. And let’s outlaw everything cause council knows best. It’s a paradox.

 

[Tubetec]

I was able to grab the Thermo top workshop manual , its a pleasure to read appart from a few strange translations , the one I got a giggle off was the reference to a particular pump not being 'self sucking' ,where self priming is the term they were after .

I was able to check the resistance of the glow plug , that measures good ,
Theres minimal soot in the exhaust port so it doesnt look like the unit had much use ,like I had suspected .
I found a USB to serial port adapter I had lying around , its picked up by the Webasto test tool software , only remains to connect it up to the burner and check for any fault codes , I'll do that tomorrow .
Its really nice you get the burner stats in real time ,any tweaks you do to the fuel/air mix are visible imiadiately , flue gas analysis would be the icing on the cake .

Theres plenty of do's and don't in the workshop manual , one thing they point out clearly is the machine is never ever to be back fed , ie the intake air needs to be harvested from outside the property , never from indoors , makes sence now I think about it as a blockage or obstruction in the exhaust could cause death .

Specifications for the air intake/exhaust and fuel lines are very clearly defined ,
in general the exhaust is pointed downwards after it exits the machine ,so any condensate drips away to the road , in the case where condensation is likely a 3mm vent hole is required , the usual arrangement is a coiled copper tube just after the exhaust port .
I need an exhaust that vents up and away , they specify a maximum lenght for the pipe , 100cm ,
I'm a little unsure of the units abillity to push its own exhaust gasses up a tube exceeding the 100cm limit , in any case the software will reveal any issues long before it becomes a problem .
The safety features of these boxes are remarkable , if any of the sensors detect a fault the burner goes into lockout mode and wont restart without reseting the power on in certain cases until the unit is seen by a service tech and reset with the Webasto software .

This thing is my favourite new toy , I cant wait to get her fired up and pumping water .
The precission and quality of the unit is breath taking in every respect , including BMW's custom made by Webasto anti-vibe mountings , a 2.9kg lump that punches out 5kw , with the effeciency approaching an electronic transformer ,
genie-rien ? hats off to the inventor

Clarkson as in Jeremy ?
Hmmmmmm I always found the guy objectionable(although I was a Top Gear fan going right back to the start ) , a right twat actually ,
I felt like punching him a few times , Ritchie Hammond should have stood up knocked the c**ts front teeth out for him ,but hes way too nice a guy for that ,

We have a housing crisis in this country , refugees are being forced into tented accomodation , our own are ending up on junk on the streets , all for the lack of a simple , easily contructable, secure dwelling space , the shortage of skilled tradesmen in electrical, plumbing and building trades back fuels the burner and raises prices across the board ,
The simplicity of the Diesel heater makes tonnes of sence to bring autonomy to simple self contained dwellings .
Please though ,be wary of the air blower Vevor heaters with the tank directly above the furnace , at very least use the German install methodology from the Webasto and dump the 'Googlish' translation from Chinese ,if it even has one .
As I mentioned earlier several boat fires have been attributed to Vevor heaters with poor installation , the same applies to any make of heater in a poor state of service .

Lets accentuate the positives ,but not white wash the negatives either .....
Cheers guys ,

 

[AnalogPackrat]

I was able to grab the Thermo top workshop manual , its a pleasure to read appart from a few strange translations , the one I got a giggle off was the reference to a particular pump not being 'self sucking' ,where self priming is the term they were after .

I believe there's a pump supplier in Nantucket that makes those.

 

[Tubetec]

There might be a funny Limerick in that ,
there was once a girl from Nantucket .......
If I continue I'll be shot down in flames by the righteous brigade .