Main Equip' Bonding & New CCU

[Lioned]

When installing new CCU its a must to have 16mm earth and 25mm tails,yes ? Otherwise dont install is what i've been told.
What about main equipotential bonding to gas and water and maybe others like oil ? It should be 10mm but supposing its not practical to get to it without considerable expense/disruption ? Could this be left as code 4 ?

Also,many houses will have some kind of bond to earth on the water but maybe only 4/6mm
could that be left as code 4.Thanks.

 

[telectrix]

you would probably find that 6mm bonding to gas/water is capable of carrying the PFC so, as long as it's securely connected, and gives a good continuity reading, if it's a ballache to replace, then i would give it a code 4.