excessive sludge and corrosion

[alb000000]

I have a vaillant boiler eco plus that came with a 5 year warranty.
On the last service no issues were found ( although the chamber wasn't physically opened - not required by the manufacturer as it would then require new seals)
A water sample testing came positive and was advised to have the system powerflushed.
I instructed a different firm to powerflush the whole system , boiler and radiators and inhibitor was added.
7 months later I had a fault because of a dirty ignitor. An engineer attended and found the following problems
1) cracked flue connector
2) warped flange Heat exchange
They wrote on the report that this was due to a backup on the condensed pipe.
a subsequent engineer attended and after inspection noted excessive sludge and corrosion and high turbidity of a sample of more than 1000 ppm
The manufacturer is now refusing to pay under the warranty as he claims that this is caused by something external to the boiler , he says I should turn to the firm that did the powerflushing.
They have abandoned the claim of the blocked condensed pipe as it happened in the middle of summer and the appliance would automatically shut off .
They are however sticking to the theory that the contaminated water is the cause of all the damage
Having had a long and seemingly thorough powerflush done 7 month prior it seems unlikely to me .

I would like to know whether a boiler malfunction , or the cracked flue or an overheated and warped heat exchanger could be the cause of the water contamination and the sludge and corrosion

Many thanks

 

[Scott_D]

this sounds like a right muddle if different people getting involved.
Did the installer do the servicing?
Is it some type of pay monthly insurance with a service?
Was it was shut off until the cracked flue and warped heat exchanger fixed?

 

[alb000000]

this sounds like a right muddle if different people getting involved.
Did the installer do the servicing?
Is it some type of pay monthly insurance with a service?
Was it was shut off until the cracked flue and warped heat exchanger fixed?

initial boiler was on govt replacing scheme firm no longer exist they contracted the installation to installer but he was their clients not mine
The services where carried by British Gas and then Homerserve both with whom I had annual maintenance contracts. The last service was by Homerserve ( who is associated with Vaillant ) confirms that everything was according to manufacturer instruction service . They advised me to have a system clean and I did a powerflush with a company member of the Powerflush association , however they dont seem to around anymore.
When Vaillant came for the fault, they cleaned the ignitor it and the boiler started . However following a discussion whether this call out would be chargeable if it was related to an external factor , another Vaillant engineer came and opened the chamber, he noted excessive corrosion , warped flange and said the bolier was not safe and not commercially reparable so shut it off and said I would need to replace it and would not be covered by the manufacturers warranty .
As my boiler was used and serviced according to Vaillant instructions , I am trying to claim under their 5 year warranty.

 

[Aquarius]

I'm not sure if it's worth anything but was the installer of the boiler a Vaillant approved/recommended installer? If it's overheated then yes parts can start to fail as a lot are plastic.

 

[alb000000]

I'm not sure if it's worth anything but was the installer of the boiler a Vaillant approved/recommended installer? If it's overheated then yes parts can start to fail as a lot are plastic.

But could the failure of any internal part result in contamination of the water?

 

[Scott_D]

But could the failure of any internal part result in contamination of the water?

No it would be from muck in the radiators.
Chances are the system wasn’t flushed when fitted as it would have been done as quickly as possible then onto the next.
That said the main heat exchanger shouldn’t have failed within 5 years.

 

[alb000000]

No it would be from muck in the radiators.
Chances are the system wasn’t flushed when fitted as it would have been done as quickly as possible then onto the next.
That said the main heat exchanger shouldn’t have failed within 5 years.

Thank you but I am trying to understand this .the exchanger was inspected during service on the and no corrosion was found . I was advised 2 weeks later that water came back from testing as positive. and then a powerflush was carried out on all the radiators and the boiler 10 days after that. How would the boiler be found so corroded that it is behond economical repair 6 months after that. ? Did the damage heat exchanger caused the contamination and new corrosion or the corrosion and contamination cause the damage to the heat exchanger ?