Weissmann vitodens 100 big problems

[Terry2010]

We had the above boiler installed 2 years ago as part of a new extension. The only issues we had to start with was the pressure would occasionally fail and more water would need to be put in the system (4 times 2 years). Last december we found the hot water would not stay at a constant hot temperature.
The water gets to temp on the boiler then the boiler cuts out and the water gets cold then hot and cold etc.
We called Weissmann and their guy cam around and swapped the Heat exchanger plate saying the system had debris. This didn't fix the problem and he advised a system power flush. The power flush was done at the time of installation so we were a little concerned this needed doing 2 years later. Our plumber came round and flushed the system and stated that they didn't think it was as not much debris came out and the problem wasn't fixed! 2nd weismann guy came round and swapped a diverter valve and gasket? this fixed the fault and hot water came back.
3 weeks ago the problem appeared to come back although not as bad yet. Called Weissmann their guy came round said there was debris in the system and swapped the heat exchanger plate. I said this was what the first guy did and probably wouldn't work but he insisted and the problem wasn't fixed! He said the boiler hadn't ben cleaned and showed me black water coming out the system. He also agreed to swap the bottom half of the boiler and told us to get it cleaned.
New part arrived and was installed still no fix engineer said the heat exchanger was blocked and needed cleaning (turns out he had a fused an external controller on the heating system). So now we had not hot water and no heat in the house and snowing outside 2 children under 3 etc... Next day our plumber arrived noticed the Weissmann guy had fused the controller and got the heating back on cleaned the boiler and released a stuck valve in the system no fix for the hot water. Phoned the Weissmann engineer who then stated the heat exchanger plate was now blocked by system debris and that they would not help any further. My plumber removed this and washed through. small particles came out but not enough in my limited experience and his considerable experience to cause a block. hot water was back but cooling to luke warm rather than cold!!!! Now four days later hot water is doing the hot cold thing again and getting worse. We have no idea what to do other than new boiler which we can't afford and we can't afford to pay our plumber to keep cleaning the system.
Any advise or help would be greatly appreciated as we are desperate..

 

[Agile]

You seem to imagine that there is a simple fix that you can do yourself like pushing a button!

Of course the real world is not like that. If there is dirt in the system an early help would have been a £100 magnaclean or even a £15 gauze filter to stop dirt getting into the boiler.

Based solely on what you have said its not possible for me to say whats wrong. Clearly dirt is a major factor although the diverter valve sounds as if failed which is a known fault on that model.

All I can say is that you will need to come to terms with paying somebody competent to come and diagnose the current problem and do whatever is necessary and take action to prevent it happening agian.

Tony

 

[Terry2010]

Hi Tony

Thanks for the quick reply. I think it is obvious from my post that I am not expecting a quick fix but I am looking for a relevant opinion on where to go.
I have proffessional plumbers telling me they have cleaned the system twice recently and the plumbers who installed the unit saying they did it at the time. On the other hand I have a Weissmann field guy telling me they have not. Weissmann tech support for the record think its the modulation unit and the second Weissmann engineer said that dirt in the system is the first excuse that they are told to go for before replacing the diverter valve(missed this on previous post) and fixing the hot water for 4 weeks.

I have been told about the magnaclean but as you said this would have been more usefull comming from the original installers.

As for money I have spent over £700 on cleaning as per Weissmanns advice and I still have no consistant hot water and a little worried about how much money I need for a resolution.
Onthe other hand I have a quote for £3000 to replace the boiler.

I am in Guildford if you could recomend a competant engineer as I have lost faith in all concerned in this so far.

 

[Agile]

There is only one cleaning which is needed and this is when the boiler is fitted and that work should have been guaranteed.

Just fitting a new boiler will not solve the problem without power flushing the system will just create the same problem with the new boiler.

If its the old 100 then I would come to you and just replace it with the same for £1400. If its a new 100 then about £1600.

There is a firm which specialises in power flushing. But a magnaclean and a gauze filter on the return will probably be better and certainly cheaper.

There is a lot of misunderstanding about "flushing". This can be as good or as bad as the operative. Power flushing takes about 4-5 hours and uses about £40 of chemicals.

How long did the installer take with the work? Why did he not guarantee his flushing?

Perhaps more to the point why did you pay him more to do it again when he says he has already done it? Did you see him doing it?

Tony

 

[Terry2010]

Hi Tony

The original installers cleaned the system at the time of installation and even showed me a bottle of chemicals they used. Can't remember what this was though. These original installers however were asked to leave the job by our project manager as the boiler failed to meet saftey standards and I believe they were reported to Corgi. The following guys (the ones we ask to come back and clean the system this time) had to lower the system and check all of the previous work to conform to safety standards.

I am expecting the second bill now as these Plumbers have come to clean the boiler for a second time based on Weissmann's engineer suggestion and found little in the way of debris and in his words certainly not enough to block a good system. So I am expecting him to bill me for wasted time.
The first time they came round in December they were there most of the day and on completion gave us a discount as they didn't find significant debris in the system (My wife was there all day with them).

The Weissmann people said the water needs to and should be perfectly clean if this had been done but our guy said that no system would be perfectly clean ever. So in my business I would start to wonder if the uint is fit for purpose in the real world.

Thanks for your suggestion on a new boiler I will discuss with my wife (Would this be new or second). How do I get your contact info?

I can't help but feel a bit daft about getting another Weissmann especially as there has been bloked valves and the prob with the diverter valve regardless of 'dirt in the system'. The new quote was for a Worcester and more powerfull than the vitodens 100 as our house is 4 bed 2 bathrooms and we couldn't run a shower and a tap let alone two showers (when it was working).

 

[Agile]

That was for a 24 kW old type or for a 30 kW new type. You contact me through my profile.

However, I dont really suggest that because its not solving the basic problem which you have of an existing boiler which is not apparently working correctly.

I would not expect you to be able to have two GOOD showers on together with a combi although a 35 kW will just about give two FAIR showers.

Tony

 

[thefloosyonthebeach]

If its the old 100 then I would come to you and just replace it with the same for £1400. If its a new 100 then about £1600.

That was for a 24 kW old type or for a 30 kW new type. You contact me through my profile.

Tony, why do you advertise so much?
Your last comment is almost aggresive advertising. Oh well, the mods must take a cut I guess.

 

[Gasman77]

Yeah mods, Why don't you do something about it??

 

[thefloosyonthebeach]

Yeah mods, Why don't you do something about it??

In his pocket I guess. Nothing has ever been done and nothing will. He adds too much to the site (knowledge) for the mods / admin to delete him, even if he does advertise his costs.

 

[Gasman77]

Adds to much!!! for Christ's sake don't inflate his ego anymore than it is - he won't be able to collect his £84 fixed price repair fee!

 

[thefloosyonthebeach]

Adds to much!!! for Christ's sake don't inflate his ego anymore than it is - he won't be able to collect his £84 fixed price repair fee!

IMHO he is pretty good at boiler repairs. I would not agree with his comment that the 'experts' on here are the best 2% in the country. Whilst Tony is vey well 'versed' in electronics, he is poor on 'hydrolics' of boilers.

He didnt even know a Prima CF existed! He wasnt the only one though! If thats the top 2 percent.... god help us!.

Im a boiler 'repairer'. I just dont ham myself up as the 'gas guru'.

www.thefloozyfor83quid.com

 

[Gasman77]

I just think he is a strange man

 

[Happyplumber]

from what you are saying even with a 35kw boiler you will not be able to have two showers as tony says .because you said if another tap is open its diffcult so the flow rate is not good enough

the size of your property plus two bathrooms should have had an unvented system installed,with pehaps a upgrade of the mains then you would know what its like to have a proper shower

The combi is just a bad compromise in your situation

Now the people from veissmann dont have their own engineers but loca service agents and have their own opinions did he take away a water sample? or this was just his presumption

alot of these SERVICE AGENTS are second rate engineers and unfortunately will blame fault on anything,because they dont have a clue on how to repair the boiler ,it will take veissmann a few years to weed out these cowboys but until then your stuck

The hydraulic block is virtually the same as any other boiler using grundfos hyrdrualics; and can be stripped apart and cleaned and put together,there are known issues with the earlier model and they should have known what to change

he magnaclean is cheap but not fully effective filter ideally you want to have spirovent magnabooster fitted ,this stops magnetic as well as non magnetic debris

I repair all sorts of boilers and have been on the veissmann installer course,the early models were riddled with issues but they seem to have ironed them out now

personally i would have stripped your boiler down cleaned the hydroblock changed the parts as necessary and cleaned out the plate heat exchanger,nothing complicated about this job and all done in under 3 hours ,with full guarantee the boiler will be working perfectly

 

[petit_pablo]

Can the OP please look again at the boiler and call it viessmann not weissmann.

 

[The Baker]

If the original poster does decide to replace the boiler he should seriously consider the 36KW Intergas Combination Boiler especially if he has a suspect system where magnatite is concerned. This appliance has no plate heat exchanger or diverter valve.

Tim