New boiler - who should I believe?

[Destroyer2813]

Although I've not participated in this thread its nice to see someone come back and be appreciative of the advice given, seen as we give it out for free in our spare time

 

[Mrs Tara Plumbi]

Just to throw in a word.
In my life of living with many heating systems I prefer a combi - and we have 5 in my household. (My Husband - the heating installer doesn't agree with me for all the reasons you read above).
The non-stop water when the hot tap is running for hours is good! You know all that....

Wanted to add there are lots of UF heating systems you could consider for the new room - don't rule it out. The cheapest installation option is probably electric UFH - we have it in parts of our house and regularly install it in others.