Megaflo pipe bore - building regs?

[neeway2000]

Desperately hoping someone can help us.
Our new-built (2005) building has 14 flats, each with a megaflo boiler installed. Since moving in we have been pushing the building firm to get us log books to ensure that the boilers were commissioned, and finally they have sent around heating engineers to inspect and commission, but two companies have now been and both have refused to commission the installation because they say the overflow piping is the wrong bore, is unsafe, and does not meet building regulations. "How did this get past NHBC inspection?" they both said.

However, when I speak to the NHBC claims department I am informed that building control and regs do not go down to that level of detail. Is this correct? We currently have two conflicting views on building control/regs!

I am now unclear whether I can legally require 'someone' (NHBC or builder?) to correct the piping. The NHBC say they are just a mediator, and it is nothing to do with them - when according to the plumber it is the NHBCs mistake that this was not picked up at inspection!

I need solid information/documentation (rather than hearsay) concerning building regs that can be used to enforce an adequate resolution. Anyone know where I can get it?

Secondly, based upon experience I expect the builder to suggest replacing our megaflo boiler with a cheaper unpressurised system that does not require the pipe work to be redone, and that the NHBC will agree with this. However, this is a bad solution as we would lose the benefit of a good unvented system - eg good water pressure, efficiency etc. Anyone know how we can avoid this?

Sorry for such a long question, but we've been struggling with this (and more) for ages!

[bobplum]

hi
nhbc are correct in saying that they dont go down to that level
this will come under the builders liability they employed directly or indirectly the plumbing contrators to install the system its there duty to ensure all contractors / sub contractors are fitt for the job,ie insurances qualified to do the job etc ie boilers fitted by corgi qualified engineers and so on to fit unvented systems you have to a ticket to install
id go back to the builders they have a legal duty to get the plumbing company back to rectifier and make good dont be fobbed off if they tell you to contact the plumbers direcct you bought the house off them failing that take legal advice
good luck

[neeway2000]

Many thanks for the reply.
I have now uncovered a useful piece of info. Been onto the manufacturers website and read the installation manual, which contains the specific regulations and sections of the reg guidelines that must be adhered to during installation, and weren't! Have emailed this to the builder and NHBC. Hopefully they will agree that there is a regs issue and take appropriate action - and will realise that we now have a more solid case which we 'could' take to magistrates court.
Cheers