Thank you Szymon, great to see you here and thanks for the valuable insight!
Do Vaillant themselves use their ‘peak’ output values for sizing recommendations to their installers, rather than the nameplate rated outputs?
I’m very interested in your experience of the 7kW units being noisy at full blast; have you investigated the cause of the noise? Is it fan/compressor related, or vibration resulting in internal components resonating/contacting against each other, which could be solved by applying ties and foam tape?