Rumbling /vibrating noise on start up of Ideal Isar HE24

[tilla tech]

Hi
My parents Ideal Isar combi, started playing up earlier this yesterday. It was making a rumbling noise so my mum turned the boiler off then called me.
I took along a newly qualified Corgi/Gas Safe friend.

Whenever we reset or switched on power, after 3 attempts to ignite, the boiler showed flashing L/F fault code, which according to the Manual could be anything from gas valve to condensate block.

We initialy cleaned the condensate trap and pipe. Then we worked our way thru the diagnostic flow diagram and found the spark igniter gap had widened from 3mm to appx12 mm. We pushed the electrodes together to 3mm and the boiler managed to light up but after about 30 secs the loud vibrating/rumbling noise could be heard at which point we switched the boiler off. We tried a few times to switch on but same sounds.


I did record the vibrating/rumbling sounds on my friends mobile so I could
upload onto the web for you to hear but forgot to get the sound recording from him. Any how we had a look at the forum for any clues and found someone suggesting that the burner chamber was not sealed at which point we found that some of the screws were not tight so those were tightened but still same problem.

The fault code does not show up during the breif 1.5 mins that it is switched on before it rumbles.

Corgi/Gas Safe friend reckons it could be a blocked flue.
Any ideas on what we could try?

Thanks

 

[Agile]

His lack of experience sounds dangerous!

Without hearing the sound its difficult to guess.

My best guess is that its modulating back and the mixture is not set correctly.

Get him to use his Flue Gas Analyser to check the mixture and correct it if its out of adjustment.

Tony

 

[plumbings83]

before anything worse happens, you have to consider other options aside from recording the rattling sound your pipe makes or else you'll face bigger problems than that...

i suggest you go to my website and maybe you'll find it helpful:

 

[kevplumb]

do call outs to the uk then do you

 

[Agile]

i suggest you go to my website and maybe you'll find it helpful

:

Since you web site address is not quoted in your profile I dont see how you expect us to do that!

In fact there is no email or telephone information either?

If you are in the USA then I would wonder why you are posting on a UK site anyway?

Tony

 

[shambolic]

Air gas mixture fault sounds the most likely. Possible moisture in gas valve? Black doughnut flue seal not in properly?

 

[Garfeild]

If it sounds like a farting noise check as Shambolic says,also check working pressure as if very low can cause the same noise.
If its a rumbling clonking noise,could be pump stuck,or plate hex restricted as boiler always goes to dhw first,check for pressure gauge needle bouncing around when it makes the noise.