hi there i have just purchased a central heating kit from Band Q the usual 7 radiators plus combi boiler valves flue etc .
on the boiler it has the gas inlet at 15 mm, i have been told by a lay man that it has to be 22 mm to feed the gas i am not doing the gas side of things but was wondering if this is true to have 22mm does this have to go all the way back to the meter . any info would be appreciated