Resonating noise cylinder vent

[speccy]

We have just had some rework to our thermal store now theres an issue when the boiler pump starts up theres a weird vibrating resonating noise which starts quiet and builds. If I feel the top vent pipe its vibrating. If I turn off the boiler pump then back on it seems to stop the noise and vibration.

Not nice though at 5.30 am though any ideas what might be? Grundfos pump is about 2 years old thanks.

 

[darren6645]

Sorry I'm not helping but I have a similar problem that I've tried to eliminate but after 3weeks it's come back, not as bad quieter than before. It only does it when the boiler fires up and is what I'm calling max flame once the set temp is reached or somewhere near the flame backs off and the noise goes altogether?
I've drained, flushed, had cleaner circulating for 2 weeks, drained and flushed 4 times new circulation pump fitted, refilled with inhibitor and noise reducer has been totally silent since doing the work but I have heard it again the last two days, no where near as bad but its there again.

 

[ianmcd]

which thermal store ? and which boiler ?

 

[darren6645]

which thermal store ? and which boiler ?

Hi Ian we've spoken before.
Mine is Flowmax 180 thermal store and vaillant ecotec plus 418 boiler.