Webasto heater: frequent burner replacement

[alanwilson]

My Webasto Air Top Evo 5500 works fine for a few months, then gradually starts needing several start-up cycles and eventually won't start up: the burner is clogged by hard carbon deposits & needs replacement, about every year. I've had it checked for correct CO2 emission etc.
I asked Webasto tech support some questions on 3 occasions and got different answers from (presumably) different people:
1. Is red diesel worse than white?
- Red diesel is not necessarily dirtier but will degrade over time.
2. Should the heater, like a diesel engine, be run hot at least occasionally?
- Running the heater hot periodically will assist the burn of of soft carbons; the hotter the heater burns the better.
3. If so, how should this be done, eg turn the thermostat fully up or run on boost?
- The best way to run as hot as possible is to turn the thermostat fully up.
- It is not necessarily better to run the heater with the thermostat turned fully up.
- Leaving the heater on boost will most likely not have any positive effects.
4. Any other ways of running hot?
- Try running the heater on paraffin for an hour, which will clean the inside of the heater exceptionally well.
- Only run on paraffin as a last resort to extent the life of a burner slightly.
- Using a blowlamp on the burner should indeed burn off soft carbons.

So red diesel is not the problem; the heater should be run hot; turning the thermostat fully up is the best way and is not necessarily better; running on paraffin will clean it exceptionally well and is a last resort; using a blowlamp on the burner should work.

I've also had the suggestion of soaking the burner in hot concentrated sodium hydroxide solution overnight.

Has anyone else had this problem? And found a solution that works? Or can comment on which of Webasto's contradictory statements are right? Thanks!

 

[NormanS]

Mine is an Eber, but I am sure that they are the same in principle.
I was advised to use diesel fuel of DIN EN 590 spec, which for me means white diesel, because the red diesel available to me is Gas Oil, which has a higher sulphur content, and a lower Cetane rating. So either use white (road) diesel, or make sure that the red that you use, complies with the required spec.
Hope this helps.

 

[JerryHawkins]

Same issue with Eberspacher

I've replaced my burner a couple of times in the last 5 years or so. I bought a small 'industrial' ultrasonic cleaner, which heats in addition. This breaks up quite a lot of the hard carbon deposits, but not all. Still need to do a bit of manual 'poking' with a small implement. The ultrasonic/'poke' cycle is repeated several times to get a reasonably clean burner. I have two burners currently and when the problems begin I swap over (takes me a couple of hours) then clean the dirty one at leisure ready for the next time.

Should add - I use white road diesel unless away from the berth for extended periods. It does make a 'huge' difference to the amount of carbon deposit and how quickly it builds up.

 

[alanwilson]

Jerry: that's very helpful. Could you give details of the ultrasonic cleaner? My heater is fed from the engine tank, so running it on white would mean installing a separate tank; not a trivial job.

 

[JerryHawkins]

Ultrasonic cleaner

This is like the one I have:

http://www.ebay.co.uk/itm/0-44G-2-0...ultDomain_3&hash=item27c7d64a30#ht_6974wt_950

The price is quite a bit less that a new burner, so has paid for itself! My white diesel 'temporary supply' is from a 20l plastic jerry-can and I use a standard Eberspacher 'dip-tube' into the filler. This has a 1/4 turn tap at the top and it then Tee'd into the feed from my 'red' day tank. I can then easily switch from red to white and back as I need by opening/closing two valves.

 

[alanwilson]

Jerry

Very helpful: many thanks!

 

[Trundlebug]

Best way to run it hot is to turn up the thermostat to full, and run it on a timed basis (e.g. on a timer) rather than via the thermostat to control temp.

That way, when it's running it'll be running hot and flat out, otherwise it will be off.

I think if you do this you needn't worry about plumbing in different fuel types etc.

Worth a try. You may need to fit a sophisticated timer if you use it a lot, to automate the switching.

 

[Martin_J]

Not sure what your burner is like on the Webasto but with my Eberspacher I find that it needs to be run on paraffin for a seven hour session in order to de-coke it. I do this once a year.

Previous postings of mine have shown photos of the inside of the burner both before and after a six hour run on paraffin. (Yes - it did need dismantling twice for this and therefore needed two new burner gaskets).

 

[Martin_J]

This thread shows that Eberspacher (I know it's not Webasto but they are not so different) recommend a run on paraffin to decoke and also includes the link to my thread showing photos.

 

[alanwilson]

Martin
That settles it: paraffin it is. Many thanks for your very helpful references to the previous posts; and to all of you who keep this forum alive with hard-gained knowledge.

 

[NormanS]

That is precisely the arrangement that I have, except that I installed a two-way cock instead of a tee piece. The original cock on the main fuel tank is difficult of access.

 

[Scarboroughsloop]

So should (or could) these be run on paraffin full time?

 

[Ex-SolentBoy]

I have an Airtop 5000.

If left unused for more than a week it never starts on the first try but always starts on the second. That was the same from new, so I guess it can't be a build up in my case.

We have only ever run it on red diesel.

 

[Marsupial]

My webasto is now 9 years old, has never had any attention or needed it, in the winter in the UK we would switch it on in November and off in April - the thermostat did the rest. In my domestic boiler at home (when I lived in the Uk) we had oil fired heating, correctly jetted it ran on red diesel with fuel set, the same mixture as I have in the boat - wasted lots of money having the boiler serviced, engineers could nt find any soot to remove - I suspect the webasto innards are just as clean. IMHO fuel is the reason why ebbers and webastos fail, sorry I sound like an advert - I don't have any connection with fuel set but their product has never let me down and it does do exactly what it says on the tin. AFAIK fuel set is the only additive recommended by ebber because it leaves no residue.

 

[pcatterall]

I have an Airtop 5000.

If left unused for more than a week it never starts on the first try but always starts on the second. That was the same from new, so I guess it can't be a build up in my case.

We have only ever run it on red diesel.

this is often because the fuel in the pipe has 'disapeared somewhere' and the pump needs a couple of start attempts to get the supply going again.

 

[alahol2]

So should (or could) these be run on paraffin full time?

I've run my Eber on paraffin for the last 6 - 7 years without any problems. Having said that it doesn't get an awful lot of use, probably only 30 - 40 hours each year.

 

[SimonSolar2C]

I've run my Eber on paraffin for the last 6 - 7 years without any problems. Having said that it doesn't get an awful lot of use, probably only 30 - 40 hours each year.

Maybe this is my problem?
I just installed a webasto compatible 2kw heater and it only runs for about 1 hour then I have to remove it and clean it out. Full of gunk and goo.
Maker says it needs new igniter but that's only used at startup right?
So I don't understand why it clogs up. Using white diesel

 

[David2452]

Maybe this is my problem?
I just installed a webasto compatible 2kw heater and it only runs for about 1 hour then I have to remove it and clean it out. Full of gunk and goo.
Maker says it needs new igniter but that's only used at startup right?
So I don't understand why it clogs up. Using white diesel

What is the exhaust CO2 % reading after service?, obviously you are not getting a clean burn, this could be caused by a slow air motor, damaged burner gauze, faulty fuel pump or just rubbish fuel. If by igniter you mean glow pin then yes you are correct that it only functions during the start sequence and during the shut down cycle so will not affect normal running burn rate. By "Webasto compatible" do you mean a cheap Chinese clone?

 

[Big John]

I've run my Eber on paraffin for the last 6 - 7 years without any problems. Having said that it doesn't get an awful lot of use, probably only 30 - 40 hours each year.

I only use Kerosene on my Eber. Runs a treat and clean as whistle with no smoke on start up.
When I used red or white diesel always problems with sooting up. I do have a separate fuel tank.

Quote from http://www.letonkinoisvarnish.uk/Eberspacher_Intro_1.html

Which fuel do we use?
After problems when we bought some bad red diesel we tried Kerosene, standard 28 second central heating oil.
At that time the heater was very close to needing a 2000 hour service and was smoking.
As soon as we changed there was a significant improvement, it burns cleanly with virtually instantaneous starting even in cold conditions. The smoking stopped and despite running on lowest heat setting most of the time for about a further 3500 hours the D2 has not shown any signs of needing a service. Derek highly recommends Kerosene.
An Eberspacher technical representative told us that the Ultra Low Sulphur Marine Gas Oil burns almost as clean as premium kerosene (paraffin) so he advises it is not worth fitting a separate tank for kerosene.
It may be difficult to find a kerosene supplier for small quantities, most deliver and specify at least 100 liters.
We found a hardware store in Bridgnorth Shopshire, W Powell & Son, who have regular deliveries and sell it in small quantities.
If you find other central heating oil suppliers who can sell in small quantities tell us and we will list them here