Valiant eco-etc 624 system boiler suggestions.

[Christopher buzzard]

I have the above boiler. 1 year old and it’s developed a strange noise after the boiler has been running for 3-4 hours. It happens when the temp in the boiler is dropping and the burner kicks in and starts to go to full flame. The noise starts loud then slowly quiets down. Lasts maybe 20 seconds. I haven’t personally witnessed the sound. He recordered it for me. I have serviced the boiler (full strip down) and found nothing unusual inside. He has an a S plan system with only the boiler integrated bypass. No external Automatic bypass. It doesn’t make the sound all the time. I’ve tried to upload the video to this thread but keep getting an error. Has any1 experienced this before?. Shall I just call vaillant out on warranty?

 

[jtsplumbing]

Get Vaillant out don't mess around with it warranty call poss faulty gas valve.

 

[Vee]

Has the bypass been set up? Its adjustable and can make all sorts of noises if not set correctly for the system from a chirping bird, squealing pig to a steam train or jumbo jet.

 

[Christopher buzzard]

Wasn’t aware it could be adjusted. Will check the manual on how to do it and also try to get the sound clip posted on here.

 

[Last Plumber]

I have the above boiler. 1 year old and it’s developed a strange noise after the boiler has been running for 3-4 hours. It happens when the temp in the boiler is dropping and the burner kicks in and starts to go to full flame. The noise starts loud then slowly quiets down. Lasts maybe 20 seconds. I haven’t personally witnessed the sound. He recordered it for me. I have serviced the boiler (full strip down) and found nothing unusual inside. He has an a S plan system with only the boiler integrated bypass. No external Automatic bypass. It doesn’t make the sound all the time. I’ve tried to upload the video to this thread but keep getting an error. Has any1 experienced this before?. Shall I just call vaillant out on warranty?

Like a trombone?

 

[Gasmk1]

My crappy glowworm combi makes a noise like that when you run hot water it lasts about 5 to 10 seconds.

 

[Christopher buzzard]

@Last Plumber yes like a trombone but higher pitched

 

[Last Plumber]

@Last Plumber yes like a trombone but higher pitched

It is to do with the combustion side by the sound of it.
To prove it, run the boiler and once it starts making a noise turn the gas cock off beneath the Boiler. It should stop instantly if it is that.

I have know it be a Gas valve problem but more often in cases I have been involved with it has been the heat ex.

Their Engineers blame water quality if they can do so beware!

 

[jtsplumbing]

Had one like this in Cornwall Glow Worm told me to re adjust the low range settings something to do with the baffle in the flue.