Vokera Compact 29a Shudders/vibrates when switching off hot water

[markdiynot]

Thanks to all that successfully helped before on an earlier thread regard this same boiler

Previous issue was a AAV but the shuddering was occasionally happening before the AAV issue and now afterwards

On turning hot tap off , short or long run of hot water the boiler shudders and makes a groaning sound bit like a dinosaurs growl made in films
Still works perfectly ok but does it occasionally , sometimes long shudder sometimes short vibration and shudder no particular pattern

Any ideas ?
Is it an inherent fault with these boilers
?
Anything to worry about ?
Etc etc

Thanks again in anticipation of any help

 

[ianmcd]

Could be a combustion problem, best to get it checked out, get it serviced by Vokera direct and you know it will be done properly and not a poke and go

 

[markdiynot]

thanks for prompt reply
could it be still be a combustion issue if it only happens when turning off hot water and the burners are turning off ?
Turning on hot water and hearing burners fire up is no problem ...just hear a click no vibration and get hot water
thanks again for any assistance

 

[ianmcd]

thanks for prompt reply
could it be still be a combustion issue if it only happens when turning off hot water and the burners are turning off ?
Turning on hot water and hearing burners fire up is no problem ...just hear a click no vibration and get hot water
thanks again for any assistance

yes

 

[markdiynot]

thanks again to all involved