Webasto problem

[bigcol]

I have a Webasto thermotop c

 

It stopped working, so I took it apart

And in the chamber was lots of built up carbon, small chunks which I removed.

The carbon was all around the glow plug. And the pins holes round the side were blocked

 

This also happened about 3 months ago,

 

Is this normal re coking up, normally we have it on in the morning only for a couple on full heat.

 

Is this something that folks do every 3 months or so??

 

Many thanks

 

Col

[Arphamoe]

If you do a search, there is a complete thread with detailed instructions! I followed it and it worked great! Can't find the link but enter 'webasto servicing photos'

[bigcol]

Yep I used that brilliant guild 1st time round.

 

Just wondered if decoking is a 3 monthly thing

Or could it be the diesel, or is the glow plug on its way out?

 

Col

[Paul's Nulife4-2]

Hi ya matey,

I've got the Webesto 5kw Heater, I've had it installed For 8 years and used it as a primary heating system, I've had it professionally serviced Once ! I've changeg the Glow pin a cpl of times, and last year I found a load of Hair n fluff in the fan that was causing problems, That's about it.

Have you got a Fuel filter to your unit,

Have you cleaned the fuel pump gause filter out,

Do you run it 'Hard' make it 'Work' they hate cycling.

I run mine on a timer for an hour then off for

Two, all day long, and switch to low wattage electric heating at night, Before the Webesto kicks in again in the morning.

I have been known to run a pint of 50/50 mix 28second Domestic heating oil and White Diesel through now and then,

This seems to work for me anyway.

[bigcol]

Hi Paul hope things okay with you

 

Pump gauze?? Didn't know it had this!

 

Or are you talking about the small individual fuel filter?

 

Should this produce the carbon deposits?

 

Many thanks

 

Col

[Semitrad]

I have a Webasto thermotop c

 

It stopped working, so I took it apart

And in the chamber was lots of built up carbon, small chunks which I removed.

The carbon was all around the glow plug. And the pins holes round the side were blocked

 

This also happened about 3 months ago,

 

Is this normal re coking up, normally we have it on in the morning only for a couple on full heat.

 

Is this something that folks do every 3 months or so??

 

Many thanks

 

Col

 

I would have thought that for a lasting cure a couple on full heat should do it more often than every three months.

[Dinz]

Hi. Pulled my 9kw C out after a couple of years for a check and was clear. I have a large load on it as in Caly, 5 rads and a fat boat to get up to temp.

Have heard that short cycling tends to coke them up. Now run again for 3 years and touch wood[or MDF] still OK.

What I did do was that if I start it I let it run for about an hour to ensure its blasted through and up to temp.

[Paul's Nulife4-2]

Basically, try and do all you can to have a 'Clean Burn', So this would start with Clean, Contaminat free fuel, Then work the unit hard to avoid Cycling. IMO.

Edited September 20, 2014 by Paul's Nulife4-2

[NMEA]

Basically, try and so all you can to have a 'Clean Burn', So this would start with Clean, Contaminat free fuel,

Assuming the thing has been properly installed and loaded, to acheave that (regardeless of fuel) you need an exhaust gas anayliser, thermotest software and an interface module, the major reason for premature coking since the introduction of ULSD is incomplete DIY serviced heaters just like the OP which have not had the burn set correctly. A properly set up heater should only require a service every couple of years, assuming they are used in the way they are suited and intended for, that is to warm the boat and heat the water before rising and coming home from work so around 1400 hours a year. Stripping the things down and removing the carbon is easy DIY work but that is the least important part of making sure you don't have to do it again in a few months.

Edited September 19, 2014 by NMEA

[NMEA]

Hi. Pulled my 9kw C

 

Never heard of those, are you sure it's not a Thermo 90?

[smileypete]

If second hand the mix may need adjusting as NMEA says, but I'd also check for obstructed intake and exhaust too.

 

As a temporary workaround it may be possible to burn most of the soft carbon off by feeding a few litres of paraffin though while running flat out, give it a kind of 'italian tuneup'

 

ISTR if the pinholes get blocked it doesn't take long for carbon to build up.

 

cheers, Pete.

~smpt~

Edited September 19, 2014 by smileypete

[Bazza954]

There is a guide complete with photographs on how to strip down and clean out /service webasto boiler in the FAQ section, it's the first topic.

hope this helps

[NMEA]

There is a guide complete with photographs on how to strip down and clean out /service webasto boiler in the FAQ section, it's the first topic.

hope this helps

And thereby hangs the problem, it is far from complete and very simplistic depiction claiming to be a full solution, it doesn't cover the important set up procedures just a strip and rebuild which in itself often knocks the settings off.

If second hand the mix may need adjusting as NMEA says, but I'd also check for obstructed intake and exhaust too.

 

As a temporary workaround it may be possible to burn most of the soft carbon off by feeding a few litres of paraffin though while running flat out, give it a kind of 'italian tuneup'

 

ISTR if the pinholes get blocked it doesn't take long for carbon to build up.

 

cheers, Pete.

~smpt~

Exactly right Pete, and not just used, we usually have to adjust after new installs depending on exhaust length and on forced air systems the duct length too.

[bigcol]

So waiting for the unit to stop, strip, clean away coke and install again is just firefighting

 

Does the unit have to set up stand alone, or in situ,

I have checked the air intake, and exhaust and all clear.

I wouldn't say the coke was soft either, just 2/3 brittle lumps size of peas, just where the glow plug is,

 

Next time it has to come off, I will drain all the water out and put shut of valves on the inlet and outlet rubber water hoses.

 

Clamping hoses, and then freeing air locks in the unit is a pain when reinstalled unit.

You know when the unit gets so hot, but hoses remain cool,But manage to shift these by working the hoses.

 

MNEA What would the turn round be in time send unit by post to set up correctly?

 

Col

[bigcol]

Alan. So is there a filter gauze thingy in the12v pump?, or are we talking about one of those standalone filter jobies?

 

Col

[Dinz]

Never heard of those, are you sure it's not a Thermo 90?

yeah it prob. is.

Don't need to look at it often enough to learn the pedantics tbh.

oops that's the kiss of reliability gone!

Even so principles of what said may hold true which was the main point.

[NMEA]

Alan. So is there a filter gauze thingy in the12v pump?, or are we talking about one of those standalone filter jobies?

 

Col

Webasto do not have a filter gauze in the pump like Ebers, they usually have a plastic inline filter or for inland craft needing BSS a small metal bowl crossland or Webasto aluminium bowl one,

Edited September 20, 2014 by NMEA

[NMEA]

So waiting for the unit to stop, strip, clean away coke and install again is just firefighting

 

Does the unit have to set up stand alone, or in situ,

I have checked the air intake, and exhaust and all clear.

I wouldn't say the coke was soft either, just 2/3 brittle lumps size of peas, just where the glow plug is,

 

Next time it has to come off, I will drain all the water out and put shut of valves on the inlet and outlet rubber water hoses.

 

Clamping hoses, and then freeing air locks in the unit is a pain when reinstalled unit.

You know when the unit gets so hot, but hoses remain cool,But manage to shift these by working the hoses.

 

MNEA What would the turn round be in time send unit by post to set up correctly?

 

Col

Not only firefighting but every time one strips the unit and scrapes at the burner mat it becomes degraded and reduces the time to the next strip down, frankly, despite having an ultrasonic heated bath to clean them in I rarely do them more than once nowadays. They are best set up in situ with their own exhaust system and air intake tube/silencer attached but if I know the exhaust length and silencer I can replicate it on my test bed. Current turn around on wet heaters is 7 or eight days including a four hour test.

[Paul's Nulife4-2]

Hi ya Matey,

Have you got something like This Filter Before the Fuel pump ?.

https://www.dropbox.com/s/cm4fcq1h2co52qx/IMAG0523.jpg?dl=0

In side is a Gause / Washable Filter like This -

https://www.dropbox.com/s/hugyb7a98cl6ljp/IMAG0524.jpg?dl=0

It's surprising how effective they are at keeping most the muck out.

As I said earlier, in my mind the more you can do to ensure clean fuel gets to the unit must help with the unit giving a cleaner burn,,,Could be wrong though.

It just makes me feel better.

Edited September 20, 2014 by Paul's Nulife4-2