u/FollowingOk5823

Can anyone explain what this noise is?

Following some building work during my which all of the radiators were removed and refitted, the main HE got blocked and was power flushed . This seemed to fix the problem at the time.

A few weeks later and these noises have started, and the boiler seems to be short cycling.

Can anyone give any advice on whether I should try to get it fixed or just buy a new boiler instead?

Boiler is a 2013 Vaillant ecotec plus 630. Ground floor 3 bed flat 1200sq/ft max.