Simple bonding question post new plumbing...

[iwest]

I had a new bathroom installed a short while ago, and a sparky did all the bonding.

It seems all OK, basically I have 10mm cable to the stopcock (no gas in the house), and in the bathroom itself I have 4mm cable from the shaver socket earth (fed from the lighting circuit) to the cistern water pipe, then to the hot/cold taps, then to the bath hot/cold taps, then to both the radiator pipes.

Now that all seems OK, but since then I have had two other plumbing changes and hence two questions.

Question 1: I have had a Salamander whole house pump fitted in the airing cupboard. Now in the airing cupboard the central heating pipes appear (they go under the bathroom floor direct from the boiler), plus the motorised valve, the new pump, the hot water cylinder and immersion heater plus all the pipes to the pump. Now is it advisable to bond with 4mm cable either side of the pump as it has plastic connectors or not? Or is it advisable to bond everthing in the airing cupboard anyway just as a precaution?

Question 2: The cold water tank in the loft has been replaced with a plastic one, do I need to bridge the pipes to and from the plastic tank with 4mm cable to maintain continuity?

many thanks

 

[RF Lighting]

Question 1: Is the airing cupboard in the bathroom, or is is seperate (such as on the landing)?

Question 2: No it is not necessary to link out the old / new tank pipework.

 

[ELZ4742]

a point to consider if the airing cupboard is in the bathroom.

is there a switched fuse spur in the cupboard? if so the earth sould be bonded to a cold water pipe to ensure correct potential.

plus, i was under the impression that it should be the rad that should be bonded and not neceserily the pipes. perapes someone could confirm....

 

[Spark123]

If the cupboard is accessable and within the zones of the bathroom then the supplementary equipotential bonding rules apply. The cpcs of all circuits in the zones should be bonded together and to any other extraneous conductive parts in the zones. The reasoning behind RF questioning is there have been alterations done in the airing cupboard which may affect the integrity of the bonding.
The CPC of a FSU in the zones will need to be included in the supplementary bonding, not just bonded to a cold water pipe. If the flow and return of the CH to the radiator are bonded the radiator should not require any more bonding as it cannot introduce a potential different to that of the equipotential zone.

Bedtime reading:
http://www.niceic.org.uk/downloads/NL139supp.pdf
http://www.niceic.org.uk/downloads/Pocket Guide 1.pdf
http://www.niceic.org.uk/downloads/Pocket Guide 2.pdf
http://www.iee.org/Publish/WireRegs/EarthingPlasticPipes.pdf

 

[iwest]

The airing cupboard is on the landing, not in the bathroom....

 

[iwest]

Presumably, as the airing cupboard is on the landing no bonding in the airing cupboard is required?

 

[Spark123]

Not if all the bonding was done in the bathroom and it is up to spec.