If the flue is not fitted right that would be classed as at risk and the boiler shut of also if the boiler is not getting the right pressure that is classed as at risk and boiler shut of,
the meter box not sealed is classed as not to standard,you could look back at your old gas certs and see...
The pipe does not need changing if you are getting correct standing and working gas pressure.
most combie boilers need 22mm pipe but normal boilers run on 15mm pipe,
what make of boiler is it.
i Have a fault on a potterton performa 28 when the hot water is running the central heating was getting warm,
I changed the diverter valve now when the central heating is turned on the temprature rises the 80 light comes on and the boiler switches of cools down then restarts back up and the...