Ariston boiler banging (ignition NOT pipes)

[Aristonboilerman]

Hi
My under 2 year old Ariston ACO 32 MFFI Combi boiler has started banging (like a car backfire). The banging is from the boiler unit (not pipes) and is accompanied by error messages saying ignition failure (1st or second attempt) and sometimes shuts down (error code - ignition problem). The boiler was serviceb by British Gas in July but all they did was take the cover off and look at it!
There is also (sometimes) a flame out of the flue when this occurs) ie gas being burnt!
Called out a service man but he had no idea.
Help!

 

[fitz1]

gas valve maybe passing. get a corgi in before any more use.

 

[Agile]

This should still be under warranty but is quite likely to be an installation or commissioning fault or a problem with the gas supply.

Its a very simple fault for a competent boiler engineer.

I expect the BG engineer did do a flue gas analysis measurement probably from the outside if the boiler is on the ground floor.

You need a competent engineer who has a flue gas analyser and experience of modern premix boilers. Few do!

One wonders just what your "serviceman" really was!

Tony

 

[fitz1]

agile . do you recon the mix is wrong.

 

[Aristonboilerman]

Service man who came out just took the cover off and said he had not seen one of these boilers before.
I am fairly sure B Gas did NOT test gas/flue emissions as I was with him all the time!
Am now out of Ariston warrenty as BG refused to do the items Ariston said were necessary for their guarentee/ would not change the part that Ariston had sent to be changed at each service! Stuffed really by BG!!!

 

[Agile]

Am now out of Ariston warrenty as BG refused to do the items Ariston said were necessary for their guarentee/ would not change the part that Ariston had sent to be changed at each service! Stuffed really by BG!!!

Perhaps the BG people can comment on that?

I think that you have a very valid serious complaint against BG if it has cost you your second years guarantee and you now have a fault. But that all depends on what happened at the time and what you may have chosen to not do to resolve the problem.

The obvious cause of the explosive ignition is a delayed ignition spark. This is often the ignition circuit, ignition electrodes or the PCB which controls the timing of the gas and spark.

It could be the gas settings but that is much less likely.

My initial test would be to time the delay between the gas being turned on and the spark, usually about 1 sec.

If that was correct I would strengthen the mixture on test be obstructing the air intake with my fingers to see what effect that has.

A seriously wrong mixture is difficult to test if it will not burn !

Tony

 

[fitz1]

get the flue checked out. air intake could be restricted.