Jump to content

Webasto Thermotop C Start-up Problem


Motters79

Featured Posts

Hi guys!

 

My Webasto has been working well since I installed it in Jan 2019. Been doing heating in winter and water in summer. It's occasionally played up but a reset by removing the fuse has always set it right up untill today. 

 

The last few times I've fired it up it has either  failed to complete the Ignition process or has died several minutes into a seemingly successful start-up. Today I was thinking about giving it its first decoke but thought I'd give it a go first as I wanted some hot water.  It got part way through the start up with the fuel pump ticking and the fan speed slowly building and then failed. Did it 2 more times and then lockout. So i did a fuse reset and from then on it would try to start but fail akmost immediately, even before the fuel pump starts ticking. Tried it several times and then decided to remove the unit and dismantle for a decoke.

 

So, I did the decoke and there was quite a lot of crud in there. Anyway, once it was all cleaned out and back together and reinstated I was feeling optimisistic. However it is still as it was prior to the decoke. The fan comes on and then stops, the water pump starts and then the whole thing just stops dead. No fuel pump tick and no more fan. After 3 tries it locks out and after a reset it just does the same again until another rest is required.  

 

What's going on? Anybody know? 

 

Any useful pointers would be wonderful. 

 

Thanks in advance.

 

Matt

 

Link to comment
Share on other sites

2 minutes ago, Motters79 said:

Any useful pointers would be wonderful. 

Problems with start up are vey often voltage linked.

 

Try it again with the engine running.

 

If it starts you need to review you battery management and get the batteries fully charged, check all your wiring for bad / dry connections, check fuses are in TIGHT.

If it doesn't start you have other problems.

Link to comment
Share on other sites

31 minutes ago, Alan de Enfield said:

Problems with start up are vey often voltage linked.

 

Try it again with the engine running.

 

If it starts you need to review you battery management and get the batteries fully charged, check all your wiring for bad / dry connections, check fuses are in TIGHT.

If it doesn't start you have other problems.

Thanks Alan. I dont think theres any problem with voltage. My batteries were fully charged at the time of trying to fire up. My batteries are in good condition and kept topped up by solar. I will try it with the engine going though just in case it makes a difference. 

Link to comment
Share on other sites

3 hours ago, Motters79 said:

Thanks Alan. I dont think theres any problem with voltage. My batteries were fully charged at the time of trying to fire up. My batteries are in good condition and kept topped up by solar. I will try it with the engine going though just in case it makes a difference. 

Tried it. Still no good ?

Link to comment
Share on other sites

At the recommendation of this forum I have ordered one of these https://www.ebay.co.uk/itm/WEBASTO-v3-4-USB-INTERFACE-DIAGNOSTIC-Thermo-Test-software/224140130964?_trksid=p2485497.m4902.l9144 .  It ships from Bulgaria (there may be more local sources?) so still awaiting delivery.

 

There seems to be 3 or 4 threads about failed Webasto's and approved repair workshops offer no warranty for using units designed for vehicles on boats.  Perhaps they know more than they are letting on?

Link to comment
Share on other sites

15 minutes ago, GRLMK38 said:

At the recommendation of this forum I have ordered one of these https://www.ebay.co.uk/itm/WEBASTO-v3-4-USB-INTERFACE-DIAGNOSTIC-Thermo-Test-software/224140130964?_trksid=p2485497.m4902.l9144 .  It ships from Bulgaria (there may be more local sources?) so still awaiting delivery.

 

There seems to be 3 or 4 threads about failed Webasto's and approved repair workshops offer no warranty for using units designed for vehicles on boats.  Perhaps they know more than they are letting on?

The software, settings and occasionally the inside gubhins is different. Some of the  vehicle ones arent built for constant running, and some are controllled by the vehicle software, not the Webasto brain.

Webasto Aftermarket unit is the one you should have.

Link to comment
Share on other sites

5 minutes ago, matty40s said:

The software, settings and occasionally the inside gubhins is different. Some of the  vehicle ones arent built for constant running, and some are controllled by the vehicle software, not the Webasto brain.

Webasto Aftermarket unit is the one you should have.

The unit I am dealing is fitted in a boat previously owned by somebody allegedly associated with Webasto sales at Autherley Junction.  Hopefully the diagnostics will reveal the issue.  I will update this thread when I know more as it may (or may not) assist the OP.

Link to comment
Share on other sites

You may have fully charged batteries but if you have just one high resistance connection anywhere between batteries and heater it will do exactly what you are experiencing.

 

You need to check the voltage AT THE HEATER whilst it is trying to start up.

 

 

Edited by Tracy D'arth
added news item as requested.
Link to comment
Share on other sites

1 minute ago, Motters79 said:

Thanks Tracy I will do that this AM. What s the minimum voltage I should be seeing during start up? 

Its not the minimum voltage but the volts drop between the batteries and the heater under load that limits the current through the heater on start up. You measure the voltage at the heater and at the battery as it is starting and running, the difference is the volts drop and if it is over say half a volt you have a wiring insufficiency or connection problem.

Link to comment
Share on other sites

1 hour ago, GRLMK38 said:

At the recommendation of this forum I have ordered one of these https://www.ebay.co.uk/itm/WEBASTO-v3-4-USB-INTERFACE-DIAGNOSTIC-Thermo-Test-software/224140130964?_trksid=p2485497.m4902.l9144 .  It ships from Bulgaria (there may be more local sources?) so still awaiting delivery.

 

There seems to be 3 or 4 threads about failed Webasto's and approved repair workshops offer no warranty for using units designed for vehicles on boats.  Perhaps they know more than they are letting on?

Now that could be a useful bit of kit. I only have a knackered old laptop that runs Linux (just about) but its basically scrap. I'd be dubious whether I could use it. It says compatible with all Windows OS. Let us know how it is when you recieve  it. It might be worth me getting it and borrowing a laptop.

 

My Webasto is a recon unit bought from eBay so i have a feeling it was originally fitted in a vehicle but ?‍♂️It was sold as being suitable for marine installation. Maybe the reconfigured its brain?

10 minutes ago, Tracy D'arth said:

Its not the minimum voltage but the volts drop between the batteries and the heater under load that limits the current through the heater on start up. You measure the voltage at the heater and at the battery as it is starting and running, the difference is the volts drop and if it is over say half a volt you have a wiring insufficiency or connection problem.

Ah ok. That makes sense ??

Edited by Motters79
Link to comment
Share on other sites

12 minutes ago, Motters79 said:

Now that could be a useful bit of kit. I only have a knackered old laptop that runs Linux (just about) but its basically scrap. I'd be dubious whether I could use it. It says compatible with all Windows OS. Let us know how it is when you recieve  it. It might be worth me getting it and borrowing a laptop.

If you do that (borrow a Windoze laptop) then try installing WINE on the Linux one and see if it works. may well do as the  bumph says all Windows OSs

Edited by Tony Brooks
Link to comment
Share on other sites

34 minutes ago, Motters79 said:

My Webasto is a recon unit bought from eBay so i have a feeling it was originally fitted in a vehicle but ?‍♂️It was sold as being suitable for marine installation. Maybe the reconfigured its brain?

Quite a few of the recon sellers say 'suitable for marine' but they are not. They do not like working on 'boat voltages' and they supply an exhaust with a condensation drip that allows Carbon Monoxide & exhaust gases to enter the boat.

 

Some of the sellers DO OFFER a marine exhaust for £xx extra but it appears from the number of threads on here about recon Webastos & Everspachers that few even notice that it is needed.

 

I'm all for saving a few £'s but not at the expense of safety and reliability.

Edited by Alan de Enfield
Link to comment
Share on other sites

Good news! I've got it going ? turns out the main relay had come adrift ?‍♂️ its in an awkward place so it wasn't obvious. Now its running sweet! Thanks for all your input though.

 

An issue that mine still has is a noise fan at slow speeds. It makes an awful racket as it spools up but once it reaches full blast it goes quiet (fortunately). When i had it in bits yesterday I thought I'd found the problem. The fan impeller had only about 0.5mm clearance between it and the body. I managed to increase this to about 1.5mm by sliding it up the motor shaft a bit, but it hasn't made any difference. 

 

Is this a known problem? Is it just how they are?

Link to comment
Share on other sites

4 minutes ago, Detling said:
5 minutes ago, Detling said:

Yours goes quiet at full speed?  most sound like a Jumbo taxiing to take off, better than Ebbersplutters they sound as though they are taking off along the runway.

 

On 06/11/2020 at 09:18, Tracy D'arth said:

 

Well I wouldn't say quiet exactly but much quieter than the racket it makes at first. There's a tonn of vibration from the fan untill it hits full speed like it's on a bit of a wobble. Thought maybe it was contacting the body as it was so close.

Link to comment
Share on other sites

7 minutes ago, Detling said:

Yours goes quiet at full speed?  most sound like a Jumbo taxiing to take off, better than Ebbersplutters they sound as though they are taking off along the runway.

This is not true. If you stand outside my boat next to the webasto exhaust you have to bend down to hear it and would not know it was running inside another boat or indeed walking past.

Link to comment
Share on other sites

16 hours ago, mrsmelly said:

This is not true. If you stand outside my boat next to the webasto exhaust you have to bend down to hear it and would not know it was running inside another boat or indeed walking past.

Much the same with my mankini Mikuni.

Sometimes methinks it's down to how it's installed - I've seen pics of installations on here  where the uint is dumped almost loose in a corner and with no silencer or insulation on the exhaust....

Link to comment
Share on other sites

try running it without the silencer and if it is similar to the 2 units i have had a silencer fitted. When i start up the unit in the phase when it goes from slow up to full speed i get a noise coming from the unit about half way up the cycle. If i remove the silencer i do not get it. Don't know what the cause is but it even did it on a new unit.

Link to comment
Share on other sites

4 hours ago, Tonka said:

try running it without the silencer and if it is similar to the 2 units i have had a silencer fitted. When i start up the unit in the phase when it goes from slow up to full speed i get a noise coming from the unit about half way up the cycle. If i remove the silencer i do not get it. Don't know what the cause is but it even did it on a new unit.

Possibly it’s  resonant frequency of the air intake system with the silencer fitted.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.