C/H Bonding

[tim00]

1. the boiler is cross bonded
2. the bathroom rad is suppl. bonded.
3. the incoming gas and water are bonded in to the MET.
Is this how it should be - and leave well alone? Or should some re-arrangeing take place?

 

[Qedelec]

There should be supp bonding in the bathroom between H & C.
If you have an electric shower fitted, there should be a bond from cpc connection to water pipe.
And a connection from shower cpc in switch to ceiling rose.

 

[baldelectrician]

Posted same earlier


All things connected together, in one continuous cable (min 4mm sq without mechanical protection)

from rad to all pipes then to bath, shower and lighting circuit- do not bond SELV (12 V lights) but DO bond supply to those, if in zones.

A bit fron the IEE on site guide, it's quite handy

http://www.baldelectrician.com/bathroomtemp.jpg

 

[tim00]

thank you both for the info. but the IEE diagram doesnt show continuous bonding in a single 4mm?

 

[Qedelec]

The diagram is using the continuity of the plumbing.

THINK!
Equipotential Bonding is to have ALL exposed conductive parts at the same potential so that if a fault occurs and something becomes live (even for a fraction of a second) there will be no potential difference between that and another exposed condutive part. Wet bodies conduct electricity!!

 

[tim00]

i originally asked the question to determine if the boiler cross-bonding was redundant and to tease out any anomalies. The IEE diagram still doesn't show continuous 4mm supp. bonding.

 

[Spark123]

i originally asked the question to determine if the boiler cross-bonding was redundant and to tease out any anomalies.

The boiler is probably cross bonded for continuity between pipes, i.e. where they enter the boiler they may not have a brilliant electrical cross connection and for safety, cross bonding has been installed. The cross bonding has been installed for a reason and should be treated as a "Safety Electrical Connection - Do Not Remove."

The IEE diagram still doesn't show continuous 4mm supp. bonding.

It doesn't need to be a continuous length of 4mm² cable, the copper body of the pipework can be used as a conductor.

 

[tim00]

Spark, thank you.