Vaillant EcoTEC Sustain Boiler; water leaking from bottom - better to use Vallaint's Repair Service?

theonenonly

sheenas said:

Valiant are great and often come out same day.
they have a maximum fix charge of around £200 from memory. 

So is it not £399 as the website shows?

plumb1_2

Yes it’s £399 but the good news is that’s inc vat.

most probably cheaper to get a independent engineer, and you ask them to do a service at the same time. And not just checking flue gas’s, a full service removal of burner cover and new seals .

WIAWSNB

theonenonly said:

WIAWSNB said:

That would be a good result, Plumb.

OP, I presume a magnetic filter is fitted? Do you know how to check it? If so, I'd recommend doing so - please report back with what you find. 

If you don't know how, then Google is yer friend.

Yep a magnetic filter is fitted.

And do you know how to clean it?

WIAWSNB

theonenonly said:

WIAWSNB said:

It's going to be impossible to diagnose from this side of the screen, but if the pressure drop is connected to the water loss, then you are seeing 'system' water and not clean 'mains'.
Does the water form a scale as it dries? Is it less than clear clean water?
I just don't know what to suggest. A friendly local GS might be happy to come out and diagnose the issue and give a quote, and give you the option of going FPR with one of the providers if he reckons it's worth it?
I had that happen once - the local guy didn't want to do the job (a split hydrobloc) not because it was costly or expensive, but because of the age of my boiler and the concern a new fault would be triggered as soon as he started taking it apart! He suggested a GlowWorm FPR instead.
For a three year old boiler, I'd imagine only one part has failed, and everything else is ticketyboo. And I'd imagine that replacing that one part is most likely to be cheaper than £399. 
But it's still a gamble.

(I'd recommend adding LP to your house policy when you renew.) 

I haven't let it dry yet (just been tipping the water out of the bowl and putting back) but from what I can see the water is as clear as tap water.

Sounds promising - if it's clear, it would indicate your system is in good condition.
Is it still leaking at a steady rate? 
What is the pressure reading?

Albermarle

plumb1_2 said:

Yes it’s £399 but the good news is that’s inc vat.

most probably cheaper to get a independent engineer, and you ask them to do a service at the same time. And not just checking flue gas’s, a full service removal of burner cover and new seals .

Apologies to the OP for the slight digression.
How often should a 'Full Service' be done ? Every 5 years ? Although I guess by 15 years you are potentially coming close to the end of the boilers life, so not worth doing that one?

plumb1_2

Albermarle said:

plumb1_2 said:

Yes it’s £399 but the good news is that’s inc vat.

most probably cheaper to get a independent engineer, and you ask them to do a service at the same time. And not just checking flue gas’s, a full service removal of burner cover and new seals .

Apologies to the OP for the slight digression.
How often should a 'Full Service' be done ? Every 5 years ? Although I guess by 15 years you are potentially coming close to the end of the boilers life, so not worth doing that one?

The OP boiler is only 3 years old 
full service depends on what the manufacturer states.
generally with the cheap service charge like £60 majority just stick a probe into the test points in the flue checking co/co2 levels, which would show if the burner was operating correctly. They don’t even take the boiler case off.
Full service, removing burner cover and cleaning out chamber,and fit new seal, 
Cleaning out condense trap, a common symptom is a leaking boiler when it gets full 
 Checking expansion vessel pressure, cleaning dust off heat  X , and new seals if needed.

theonenonly

Plot twist: the hot water has stopped running. Doesn't even try to "ignite" the boiler. The radiators work, thanfully.

Had someone to have a look, and he's noticed water coming out of the "main heat exchange"- I wish I took a photo, as I can't find a proper diagram or photo of it online, but there was indeed a few drops coming out. He's not sure of how to take it apart, and reckons it's a seal issue- "see, I can fit my nail in there, I shouldn't be able to".

Not sure of his abilities to be fair; he'll be back tomorrow maybe with someone else. Googling the fault of "leak + now no hot water with radiators working" points to a damaged diverter valve, nothing about the heat exchange. 

But I'm no expert, so I'll leave it to him to see what he says tomorrow.

If it is the heat exchange, I don't think it is covered under the Vaillant one time repair service I mentioned in my original post. 

WIAWSNB

theonenonly said:

Plot twist: the hot water has stopped running. Doesn't even try to "ignite" the boiler. The radiators work, thanfully.

Had someone to have a look, and he's noticed water coming out of the "main heat exchange"- I wish I took a photo, as I can't find a proper diagram or photo of it online, but there was indeed a few drops coming out. He's not sure of how to take it apart, and reckons it's a seal issue- "see, I can fit my nail in there, I shouldn't be able to".

Not sure of his abilities to be fair; he'll be back tomorrow maybe with someone else. Googling the fault of "leak + now no hot water with radiators working" points to a damaged diverter valve, nothing about the heat exchange. 

But I'm no expert, so I'll leave it to him to see what he says tomorrow.

If it is the heat exchange, I don't think it is covered under the Vaillant one time repair service I mentioned in my original post. 

"see, I can fit my nail in there, I shouldn't be able to".

This guy is a keeper. For hitting repeatedly with an inflated pig's bladder.

Ok, he might have a point - the mainX should be gas-sealed and have no route out for liquid.

Let's see what the new guy says. 

If the MainX has failed, which is a very - the most - expensive part, then you could have a claim against the manufacturer, unless they can demonstrate there was a cause for its failure. That part should last well over a decade.

They may claim, tho', that the servicing could have picked up on, say, overheating issues which have stressed it. So, I'd try and get a written opinion from the new guy as to why it failed - if it's the MainX. 

theonenonly

So, as I'd guessed, the chap I had around yesterday isn't confident about touching this. I've highlighted the area in a red circle where he thinks the leak is coming from

WIAWSNB

You aren't going to try and sort this yourself, of course? That's all gassy stuff, which can kill you deed.

It appears to be part of the air inlet side of the flue, but I'd have to look it up. 

See the black corrugated hose to the left-down from there? That, I think, will be the condensate pipe from the combustion chamber, so will lead to a syphon trap. This can fill up and block with debris over time, and cause a spill. 

But, it really comes down to what type of 'water' is coming out - is it clean mains water, system water (slightly brown with inhibitor, leaving a scale when dry), or condensate (clear but a bit acidic - does it make baking soda fizz?) 

I suggest the answer to this will determine how serious the issue is likely to be - system water likely being terminal. 

Hang on - there isn't a cold mains supply to the combustion chamber, so I can't see how it can be clean mains water. 

IF the leak is accompanied by a system pressure loss - which you suggested it could be but haven't confirmed - then it's most likely a system water leak, and hence a cracked chamber. Not good.

BUT, that's all guesswork, as I don't know that boiler type.