Covered in confusion - mains gas pipe diameter

SLastra · Apr 1, 2022

Hi
Having lived in a new build for 14 years, on trying to replace our two boilers I’ve been told the installation is dangerous (and has always been so and one boiler has been shut down. The diameter of the pipe from the mains (on one side of the house, which runs under the floor to the boilers on the other side of the house) is too narrow and must be rerun which involves taking up paving and digging a trench plus the run may be too long to be effective. It’s been non compliant and dangerous since installation apparently. I still have the original gas safety certificate sign off, my question is can I go back to the original plumber who installed and signed this off after all this time as it has been unsafe to rectify?

cjg · Apr 1, 2022

have you had your boilers serviced in that time?

SLastra · Apr 1, 2022

cjg said:
have you had your boilers serviced in that time?

Yes. British gas mainly and they never noticed it until quoting for new boilers. Apparently they didn’t do a flow test?

ShaunCorbs · Apr 1, 2022

I would get an independent engineer to conduct a pressure drop test with all gas appliances running

snowhead · Apr 2, 2022

As Shaun has said, get an independant engineer /small local company to test then also get them to quote for new boiler(s).

I would imagine B.G are just quoting like for like, in rating, for new boilers.
What it needs is a complete assessment of the heat loss for the house and then determine the size of boiler(s) required.
It may be that the total boiler rating can be reduced enough to be able to use the existing pipework.

Alternately the local company may find aa acceptable route for a new pipe that doesn't involve digging.

The existing pipework may have been non compliant but cannot have been dangerous otherwise every time British Gas, with all their experience, knowledge, trained engineers etc, have serviced the boilers and left them working they have been guilty of leaving the installation in a "Dangerous" state.

If it definitely is/ has been Dangerous, then I'd be looking at least to get BG to refund what they've charged for over the years as by their own admission they've left it in that state several times.