Poor installation. Numerous latent issues.
Installed a boiler for my elderly mother in January 2020. The initial installation was done with a O-ring/gasket missing, so it slowly leaked and cause water damage to the plaster and paint finishes on boths sides of the wall, plus the content of the cupboard. Upon the annual service, the installation was very nearly condemned as the flue was missing a bracket and thus not fully supported and there is a gap in the rooftiles. This would have left my mother without heating or hot water in mid winter. In fairness to Dyson, they did deal with the bracket issue under the warranty, but there is still a gap in the roof tiles. However, worst of all, in all of this, as my mother is hard of hearing, and the heating being off spring through autumn, we have not spotted an incredibly loud noise akin to a spincycle or moped ticking over, emanating from the system. We are informed this is due to the system not being 'balanced' on installation and we are now out of warranty by a matter of days.