Don't know if anyone is aware of this but since April 2006 all new condensor boilers must comply with building regs!
We had no idea about this until now, in the process of selling our house. Our buyers solicitors were asking about building regs for when we had a new boiler installed 4 years ago. We thought to ourselves "since when do you need Building Regs to put in a new boiler". Having checked on the web we did indeed find that this came in to force from 6th April 2006 but as ours was installed in January 2006 it doesn't apply.
Just wanted to let you know.