Earth strap for cetral heating pipes

Can an earth strap for cetral heating pipes come from a wall socket on the ring main or does it have to come from the main earth in the fuse box.
Thank you

The main Earth Terminal (usually in the Consumer unit) is used for Main Bonding of the incoming metallic services that enter the house from outside - usually gas and water supply, can include air conditioning ducts and pipes - because they can introduce an electrical potential from outside the house.

Once inside the house, pipes only need Supplementary Bonding (e.g. in bathroms, and now also for boilers). This only needs to be connected to the earth conductor of the circuits involved, so, for a boiler, you just need to cross-bond all the metal pipes, the boiler casing and frame, and the electrical circuit that supplies it. This is usually from an FCU on the Ring circuit. It should not be earthed via a plug, because a plug can be removed.

You will not find Boiler supplementary bonding in Electrical regulations though - it seems to be required by Manufacturer's Instructions or possibly a Corgi standard.

http://www.ultimatehandyman.co.uk/earthing_supplementary.htm the link might help you

the earthing in question comes from a wall socket next to the boiler. The earth cable actually goes up into the socket housing and is not connected to a plug.
Also only goes to 1 heating pipe on the combi boiler
I ask because on my old house it was slightly different and wanted to make sure its ok to have it this way.
Thanks

i'd cross bond all the pipes to each other as well just to be on the safe side.. it only costs a few pence for the clamps..